How to Fix Cloudy Pool Water

How To Fix Cloudy Pool Water

When you have a cloudy pool, it can be a very difficult and time-consuming process to get it clear. Sometimes, your swimming pool will turn cloudy overnight!

I’ll explain the reasons your pool got cloudy in the first place, then share a few methods on how to fix the cloudy water. It won’t be a difficult and time-consuming process if you follow these methods.

Before we talk about how to fix you cloudy pool water, let’s first understand what causes it.

Why Do I Have Cloudy Pool Water?

There are so many causes of cloudy pool water, but I have broken it down into three main causes.

1. The Environment

Everything around your pool can cause your water to be cloudy, that includes: weather, birds, construction, trees, gardens, the sun, people, and pool algae.

2. The Pool Filter

If you filter system is not working properly, or you’re not running your filter at least 8 to 10 hours per day, then you are at high risk for cloudy pool water.

Your filter system constantly cleans the water in your pool. Without it, you’re left with stagnant water that could become cloudy.

3. Pool Chemicals

An excessive amount of pool chemicals can cause your water to be cloudy. That includes: high pH, high alkalinity, high chlorine or other sanitizers, and high calcium hardness.

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You want to make sure you shock your swimming pool every week with the proper amount of shock for you size pool.

Sometimes you’ll get cloudy pool water after shocking. This is common and should dissipate over time. Just keep your filter running and it should clear up. Also, look into a new brand of shock (make sure you buy shock that has a main active ingredient of calcium hypochlorite). Cheaper shocks that you get from the big box retailers, such as Wal-Mart and Sam’s Club, are not the best choices.

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How To Clear A Cloudy Pool

Once you have fixed all the possible problems that can cause your water to be cloudy, now we can work on a cloudy pool water fix. Here are 3 ways to clear your cloudy swimming pool:

1. Use A Pool Clarifier

It’s always a good idea to use some sort of pool water clarifier weekly. Pool clarifiers work to gather the tiny particles that are making your pool water cloudy and bring them together to create bigger particles so that your filter will have a better chance of picking it up. This is called a coagulant which is a term used when describing blood clots.

The particles alone will have a hard time being picked up by your pool filter, so this chemical “clots” them together and your filter now will be able to trap them.

Most swimming pool chemical retailers will carry more than one form of swimming pool clarifier. Just ask if the chemical is a coagulant and you will be well on your way to a crystal clear swimming pool.

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Use this simple clarifier to bind small particles in your water to create bigger particles that your filter will have an easier time getting out of the pool water.

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2. Use Pool Floc (Flocculant)

A chemical called Floc or Flocculant is a great idea if you’re in a rush, or would like to see your swimming pool cleared up quickly.

Lets say you have a pool party tomorrow and your swimming pool is cloudy. By using Pool Floc, you can clear your cloudy swimming pool overnight (with a little extra work on your part). Floccing your swimming pool is a great method, but it’s very time-consuming and difficult.

Pool Flocculants work by gathering all the particles, that are making your water cloudy, and sending them to the bottom of your pool, creating a huge cloud on the floor of your pool. Unlike a water clarifier, this chemical WILL NOT help your filter to pick up the particles, because all of the cloudy pool particles are now at the bottom.

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One of the most under-rated pool chemicals. If you’re looking to quickly get rid of algae (and don’t mind a little hard work), use this to settle all the algae to the bottom of the pool and vacuum it out to Waste.

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At this point, you will need to manually vacuum up that cloud using your pool pump, not an automatic pool cleaner. When vacuuming, you want your filter setting to be on the “waste” or “backwash” option (if you are using a DE filter or Cartridge Filter make sure that the drain plug is removed.

[Here’s a video on how to manually vacuum your swimming pool.]

The idea here is to vacuum up the cloudy water right OUT of your pool, because putting that much dirty water through your filter WILL NOT work and will send that dirty water right back into your pool.

By vacuuming out to “waste,” it will never run through your filter system. You are going to lose a lot of water in your pool, so make sure to keep a fresh hose of running water in your pool during vacuuming.

Also, you must use a manual vacuum for the process. Automatic pool cleaners will not work and will just end up blowing the cloudy you created at the bottom of your pool, right back up. Again, it is difficult and a lot of water is wasted, but it will clear your pool in 24 hours if done properly.

3. Use Your Filter System and Bottom Drain(s)

main-drainYour pool’s main skimmer is located at the top of your pool and helps to clear the top, which does not help to collect the cloudy particles that are at the bottom of the pool. Knowing this, we need to help the filter get to those particles.

You can achieve this two ways:

  1. Constantly stir up the water, by swimming or with a pool brush, so that it pushes the particles closer to the top of the pool.
  2. Turn on the bottom drains.

Every inground pool should be equipped with 1 or 2 bottom drains, so it’s easy for you to utilize them. This will allow the filter to start pulling water off the bottom of the pool, where the cloudy particles are, and circulate the clean water back to the top.

This works great, but what if you have an above ground pool that doesn’t have bottom drains? We have come up with a little trick to mimic the effect of a bottom drain in an above ground pool.

Simply hook up your manual vacuum cleaner, as if you were about to vacuum your pool, but instead, leave the vacuum at the bottom (in the middle of your pool) and turn it upside down. Now your pool filter will be pulling water from the bottom of your swimming pool using your manual vacuum and releasing the clean filtered water up top.

These are three different methods of how to clear a cloudy pool by using swimming pool chemicals and your pool’s equipment. Check out some of our related articles to get more information about cloudy swimming pools.

If you have any questions about your cloudy pool, be sure to ask in the comments below and I’ll answer ASAP.

How to Fix Cloudy Pool Water

Happy Swimming!

The Art of Pool Care

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  • John Coppola

    My problem is not killing the algae , I can do that . My problem is removing the dead algae from the bottom of the pool the next day . I use a product called ” Sink and sweep ” it works pretty good , but my pool is a older system and doesn’t have a back wash to discharge the water out of the pool , all I have is that filter and a purge valve on top . So when I vacuum, most of the dead algae bypasses the filter and goes back in circulation into the pool , and only 20 minutes later my pool is cloudy again . What can I do ?

  • Matt Giovanisci

    You need to vacuum to waste and NOT to filter. The water you vacuum you exit the backwash port instead of coming back into the pool. You’ll lose a lot of water, so keep your garden hose in there while you’re doing it.

  • shonda

    I just used sink and sweep on my pool and my vacuum is not getting enough suction to pick up the cloud of dirt on the pool floor. will it mess up my pump if i turned on my filter? to filter the cloud of stuff on the bottom of the pool.

  • tara kehoe

    I have an above ground pool with really cloudy water and nothing I do is working to clear it, I’ve heard of sink and sweep but I don’t have a vacuum to waste valve on my pump, any suggestions??

  • Rachel Treadway

    I have tried everything- yesterday even took the water to be tested- all levels were dead on except for the one that was way low that means it won’t hold chlorine once the sun hits it causing it to evaporate as quick as you put it in. He told me to try a conditioner, using about 1/2 the container and then adding 2 more jugs of chlorine. Well, this am, it’s still the same cloudy mess. It’s blue but cloudy enough I can’t see the auto vacuum running in the bottom. I’ve run the vacuum all weekend and the pump- and still no clearness and a whole bottle of clarifier the previous weekend they told me to use? I wish now I’d just emptied the pool and started with fresh water. What to do?????

  • happycamper64

    Love the idea of using the pool vacuum as the main drain is great. I’ve always been annoyed I have no main drain and now I can at least emulate one when needed.

    For those of you that have no way to bypass your filter when vacuuming up the floccullant, I offer up the trick I have done for years. Use your shop-vac. Most are designed to handle water as long as you remove the vacuum’s dust filter. I put the pool hose into the vacuum port of the shopvac and place the shopvac where I want the water to drain (because it will be too heavy to move later) and then fire it up. I can vacuum for a minute or so, until the shopvac is full an then I unscrew the plug at the bottom and drain it out. Yes, it takes a while, but it beats having to clean the pool filter 10.000 times. This will also drain a lot less water than your pool pump would suck out to get a similar job done.

  • Karen

    Where to start if you used excessive chemicals trying to clear up cloudy water?

  • Michelle

    I understand that you need to vacuum to Waste after using a flocculant, in order to prevent it from entering your sand filter and causing massive problems, but what keeps any remaining flocculant fluid in the pool from entering your filter AFTER you’ve vacuumed the debris & returned your pump to the Filter setting?

    Call me paranoid/overthinking, but I’d like to use this to clean out some dead algae material following a Shock treatment and can’t afford to encounter any more major issues.

    Any thoughts appreciated! Thanks! :)

  • John Bullock

    I have never read such absolute rubbish and you are blatantly being coerced into spending huge amounts of money on chemicals you don’t need and processes you don’t need by following this “advice”. Do not do anything advised in this article.
    Stabilise your chemicals using a simple kit you can buy for $25. No need for more expensive unless you have major water problems.
    Check and keep the water stabilised once a week in winter, twice a week in summer.
    Run your filter one hour a day in winter, two hours in summer (30C and above).
    Shock chlorinate only if you have a major algae problem and if it recurs, pull out the lights and kill the algae that will be living in the sockets. If that doesn’t work and your pool has been left stagnant a while, replace your filter/sand/etc. Do not keep shocking, you’re wasting your money and health.
    Use flocculant only as a last result to settle in-water particles and then vacuum them to ‘waste’ > to the drain and not back to the pool. Floc is highly toxic to humans.
    If the water is persistently cloudy, also suspect your grouting.
    DO NOT keep adding chemicals as suggested in this article.
    DO NOT waste your pump lifetime and electric running the pump constantly.
    If you have a water issue, there is a simple, logical solution that this article will not fix.

  • Jason

    Fill your vacuum hose 100% full of water and attach it to the return. Remove cartridge filter and put the hose off the pump on the ground..it should siphon .aka (vacuum to waste) hurry carefully to not stir the cloud

  • Michael Minuto

    I have a metal frame above ground pool and i had a major algae problem I went to Leslie’s pool and spas and they had me buy 2 packets of shock and pool first aid I put 1 packet of shock in saturday afternoon the 2nd packet in sunday afternoon and the pool became a cloudy blue then i put in the first dose of pool first aid on sunday night and put in two more doses last night and still no clearer so my question is should I continue using the pool first aid or switch to a clarifier like you used in the video?

  • Matt Giovanisci

    If the pool is cloudy blue, you need to keep the filter running while adding the Pool First Aid. It will take about a week. I think the clarifier you’re using is fine.

  • M A L

    If the chlorine will not stay in the sunlight you need a stabilizer.

  • Matt Giovanisci

    Yes you do.

  • Bill

    A good idea that uses a lot less water is to siphon the water out through your vacume head and hose onto the ground. You’ll have to move the head around slower but you’ll only lose a few inches of water to do the whole bottom of the pool.

  • Johanna

    Maybe you need to bring your pH up by adding pH increaser so that the water will hold the chlorine, killing the alge then a little clarifyer and should be good as new. Do you have a hone chemical test kit??

  • Johanna

    Do you have a manual vacuum that hooks to your garden hose? That’s what I use on my above ground pool.

  • Dontay

    This article contains some very serious inaccuracies. You certainly should NOT shock once a week, or even because it’s the last weekend in the month. Shockdosing is a serious proceedure (not a product) it has to be done correctly or it will fail and should be only carried if absolutely necessay. The vast majority of cloudy or green water problems are at base due to incorrect high levels of Cyanuric Acid (CYA) known as conditioner or stabiliser… being continually introduced to the water by way of stabilised products… leading to incorrect amounts of chlorine. CYA is the stabiliser in multifunctional chlorine tablets. CYA is required to restrict the suns ability to remove chlorine from the water at a very rapid rate. BUT CYA also increasingly restricts chlorine’s disinfectant ability… at indeterminate levels above 50ppm it can even cause chlorine ‘lock’ i.e. it STOPS chlorine from working no matter how much is in the water and no matter what your FC readings show! Chemical makers and sellers will give a CYA range of 30-50ppm. Less than 30ppm and the sun will eat up your chlorine quicker than any disinfection activity! BUT also be very clear… what they DON’T tell you is the higher the level of CYA the more chlorine you will have to use. The correct minimum FREE chlorine (FC) ratio to CYA is 7 and a half percent. Example: If CYA 32ppm (which is an ideal level) then MINIMUM FC should NEVER be allowed drop below 2.2ppm which is 7 and a half percent of 32. CYA levels can ONLY be reduced by water dilution. Example: pump away 50% of water volume, replace with fresh water and you will reduce the CYA by 50%. Folk who use STABALISED products are continually increasing their CYA. With CYA at 32ppm then to achieve a MINIMUM FC level of 2.2ppm your pool, should be dosed to a target of 4ppm… 24 hours later FC should not have dropped below 2.2ppm… (7 a half percent of CYA) Cloudy water is almost always due to chloramines… a combination of used up ‘dead’ chlorine and ‘dead’ bacteria… (COMBINED chlorine) It’s chloromines which cause ‘red eye’ and give off a strong chlorine smell. The other main cause of chloromines is PH above 7.8… because high PH can also weaken FC’s disinfection abilities. PH should be in the 7.4-7.8 range… ideally around 7.4 because the lower the PH the more effective the disinfection ability of FC. Shockdosing means taking the FC level through the chlorine BREAKPOINT. The decision to shock the water should be based on the TOTAL chlorine (TC) reading and the level of chlormines in the water. If chlormine levels approach 0.5ppm above FC then the only way to clear them is to shock the water. Daily dosing will become increasingly ineffective. We cannot test directly for chloromines. We test for FC then test for TOTAL chlorine (TC) The difference between the readings is the chloromine level. To ensure that shockdosing is completly sucessful then it is vital to go through the BREAKPOINT. Thie breakpoint is 10ppm ABOVE the TC level. Example: TC reads 5ppm then the breakpoint is 15ppm. better by FAR to over dose and exceed the breakpoint than just fall short of it. This point is where a chemical reaction takes place, chloromines are lifted out of the water and what remains is chlorine in its free state! It is only when that reaction takes place that you will have successfully shocked the water. Fall just short and you will be doing again within a very short time! ALSO that breakpoint should be maintained for a MINIMUM of 8 hours. Shock late in the evening and test again early morning and leave circulating… if the level has fallen below the breakpoint add more chlorine! Solar covers should also be left off to allow chloromines to be ‘lifted’ out. High chlorine levels also shorten a solar covers life! The other reason to shock a pool is algae! Green stains appearing leading very rapidly to deep pea green water. The shock proceedure as outlined will clear even the most heavily contaminated water but in this case it is also wise to first reduce the PH to 7.2 to make FC even more active. Fi-Clor market a stabiliser FREE none diluting super fine powder ideally suited for daily dosing or shocking BUT in all cases liquid chlorine is cheaper by far. Always avoid using stabilised chlorine or within a couple of months the CYA will be VERY high your normal FC readings will still be there but will no longer be anywhere near sufficient to prevent problems unless you ALSO increase the amount of chlorine to stay in the MINIMUM of the 7 and half percent of CYA rule! Only by purchesing a ‘proper’ liquid regent test kit will you be able to have a trouble free pool which will hardly ever cause you problems. Tablets are a poor substitute and the use of test strips will always give rise to problems. Tenants Division market a liquid regent test kit in the UK called ColorQ Pro 7 it cost around £130 order on-line. Individule droplet regents for each parameter are sufficient for around 140 tests, replacements regents around the same price as test strips. It test for FC, TC, TA, PH, CH. also bromide if required. The kit contains an accurate digital readout meter taking the guess work out of water testing.

  • Matt Giovanisci

    Thanks for your comment. However, this is the reason I started this site. What you’ve written is accurate but confusing for the average pool owner.

    This would make for a great post for advanced readers. Would you like to submit this comment as a guest post on the site so that you can get a link to the site you’re trying to promote?

    Either way, I appreciate the contribution.

  • Dontay

    Hi Matt, I’m sorry but EVERYBODY should understand that the vast majority of cloudy water problems are due to chloromines and not other small particles that a filter cannot handle and using flocks and other such clarifiers of any description are a waste of money and THAT is why a substantial majority of folk write to complain that nothing they have tried has worked or only works for a very short time! The answer is simple… they DON’T work! They are an over hyped part of the pool chemical industries attempts to part pool owners from their money! Exactly the same applies in the industries attempts to convince owners that shockdosing should be a frequent and regular proceedure. Exactly the same applies to algae removers and preventatives (and also phosphate removers AND the seperate phosphate test kits that are needed which is the latest focus of the chemical industries attempts to part owners from their money!) Cloudy water is virtually ALWAYS down to chloromines and the ONLY way to reduce pool water with high chloromines is to shock the water and if pool owners are finding they have to do as you suggest and have to shockdose every one or two weeks then their routine water chemistry understandings need seriously correcting no matter if they are new or experienced pool owners. In a healthy pool If the chlorine levels are ALWAYS kept above the minimum levels then algae cannot take root so there is absolutely no need to buy seperate algae prevention chemicals, chloromines will be kept substantially under control and shockdosing will hardly ever be required from one end of the season to the other… and providing all other paramiters and levels are correctly maintained pool water will remain crystal clear. The root cause of virtually all pool water problems are poor maintence routines and lack of understanding about the effects of CYA leading to continual ‘fire fighting’. The pool water chemistry industry is the wolds best adept at maintaining pool owners ignorance! It is simply in the chemical makers, chemical sellers (and chemical advertisers) best interest to keep pool owners ignorant. Get the daily routines and levels correct and give your pool a rest from all the chemicles this industry wants you to continually pour into your pool… and save your money!

  • Sue

    I bought an above ground pool and put too much algea solution in. Now I can’t get rid of the cloudiness. What should I do? Please help!

  • Matt Giovanisci

    Keep the filter running 24/7. Make sure all your other chems are at the right level. Use can use a clarifier if needed.

  • Brooke Kane

    I have an inground pool, 27,000 gallons. We have tried every thing under the sun when trying to get our pool clear, and it’s still cloudy. We’ve tried a clarifier, we’ve shocked it every week or every other week. When we take a water sample in, all our levels test out perfect. Even the pool place can’t tell us why we can’t get our pool cloudy. We’re at the end of our wits here and just want to bulldoze our pool in because we’ve spent $800 dollars trying to get the thing clear this year. I have no clue what to do next as to how to clear our pool up, besides draining the water. We live out in the country, so I’m not sure if the country water has anything to do with it or not. Any suggestions would be helpful!!!

  • Matt Giovanisci

    Sounds like a filter problem now. You need to run it 24/7 and perhaps change the media, whether it’s sand, DE or a cartridge.

  • Brooke Kane

    We just changed the sand, maybe a month or so ago. We figured it was the sand too. I think it’s a filter problem tho. Like either something with one of the lines in the filter, or even those things in the sand filter that can break easily. I’m just lost as to what it could be.

  • Matt Giovanisci

    Have you tried floccing?

  • Brooke Kane

    I’ve never really heard of floccing, what is it? We’ve let our filter run 24/7 for the last 3 days and it seems to be getting clearer. It’s just not that crystal clear pool that we should have.

  • Matt Giovanisci
  • Dontay

    Cloudy water problems are very easy resolved but you need the correct testing information from your pool water in order to resolve it. There is only one way to acquire that info and that is to test it yourself. It is a big mistake to rely on pool store water tests, they are notoriously unreliable, (take the same water sample to three differnt stores and you will obtain three very wildly different results!) and also in order to raise FC to shock level with a view to gaining crystal clear water you will need initially to test every 2/4 hours. Depending on the level of contamination initial constant testing WILL be required because FC will constantly and very rapidly drop and it is vital to keep to at or above shock level with constant additions of chlorine. After the initial stages which may take at least a couple of days… you only finish shocking the pool and allow FC levels to drop when three distinct criteria have been met… 1)visually crystal clear water. 2) OCLT (overnight chlorine loss test) showing FC loss is no more than 1ppm overnight. 3) CC no more than 0.5 ppm. Again depending on the level of contamination it can take several days before those criterion are met and FC allowed to return to normal levels. Once done and water chemistry is then KEPT correct with the correct CYA/FC ratio adhered too… there is absolutly NO need to shock pool water working to some arbitrary time scale! It will ALWAYS remain crystal clear! Shockdosing is a CURE not a maintaince or prevention exercise and it HAS to be carried out in the correct way or you WILL be shocking every couple of weeks… much to the delight of the pool store! No-one can accurately test FC at shock levels unless you have a test kit that is capable of it… these kits are known as FAS DPD test kits. Many well known American manufacturers produce them, (most common are Taylor, LaMotte, Palintest) they are widely available on line (but not many pool stores stock them) they are easy to use, they are accurate from 1 ppm to at least 25 ppm FC… and not expensive to buy. Purchasing one of those is a vital requirement for any pool owner who wants continually crystal clear water and a trouble free pool. Test strips or tablets (with or without a digital analyser) only give a very rough guideline up to 5 ppm, no chemical alterations should be undertaken by relying on either of those types of test kits whatever the case… but above 5 ppm completly forget it! The other vital piece of info you need to know in order to correctly shock a pool is what your CYA (Cyanuric Acid) level is… since ALL FC levels including shock level are based on the CYA figure. (FC shock level is 40% of whatever your CYA is) that is the point where a chemical reaction takes place and chlorine begins to start killing the contamination. Without knowing that CYA figure you cannot hope to permanently clear up your water. Most cloudy water problems are caused by having CYA too high in relation to normal FC maintenance levels. That leads to cloudy and or green water because FC activity becomes slow and ultimately ineffective. The only cure for high CYA is water dilution. Another cause of cloudy water is high calcium hardness (CH exceeding 350 ppm) The only cure for high CH is water dilution but replacement fill water can also have pretty high calcium levels! Both problems arise from the constant use of very easy to use, but nevertheless… the ‘wrong’ type of chlorine. Stabilised products constantly add CYA and stabiliser free shock powder (Calcium Hypochlorite) can very quickly take calcium soaring above 350 ppm especially in the volumes that shock levels require! There is a much safer and MUCH cheaper way of chlorinating a pool. Liquid chlorine (Sodium Hypochlorite) which only adds a small amount of harmless salt is sold by most pool stores… is by a very long way the cheapest, the most economical and SAFEST for your pool option. The drawback is its heavy and bulky. However with a bit of thought and a careful decanting exercise that drawback can be overcome. Uncented bleach from your local supermarket is another option and you may find it even cheaper.

  • lemon111

    Shock is not a product, it’s a process where the chlorine level is raised to a higher than normal level in order to kill any organics (like algae, bacteria etc) in the pool. What this high level should be is dependant on the amount of CYA (stabilizer) that is in the water.

    You say to use ‘calcium hypochlorite’ which is fine, but any chemical that raises the chlorine level will still create a ‘shock’ condition ( a higher than normal chlorine level).

    Be aware that using Calcium Hypochlolrite as you suggest, WILL raise the calcium level of your pool water. If the pool owner does not want the calcium level to be higher, Sodium Hypochlorite (yes, regular liquid chlorine from the pool store) will raise the chlorine to shock level without raising the calcium level (it will raise the salt level, but this is preferable to a higher calcium level if your calcium is already high).

    The main point I’m trying to make here is that ‘shock’ is not a chemical you buy that magically clears up your pool. It’s the higher chlorine level that does the work (the bag of calcium hypochlorite might say ‘SHOCK’, but all it is chlorine in powder form that raises your chlorine level).

  • Dontay

    Sue… Algae prevention solutions don’t cause cloudy water. Cloudy water has occurred because your algae solution hasn’t prevented organics (usually algae) or bacteria from contaminating your water, both of which, in the absence of chlorine, will give rise to chloromines which appear as cloudy water, eventually it will turn green as algea starts to bloom. Chlorine at correct levels prevents organics and bacteria from contaminating your water and with the help of normal UV sunlight routinely keeps chloromines below 0.5 ppm which is the maximum level before shockdosing is required. The way to get to crystal clear water is to shock it and keep it shocked until the water appears crystal clear. Once you have achieved that AND THEN you keep your FC levels correct you will not have algae in your water so you do NOT need to waste money on algae preventative solutions’. You have just proved they do NOT work! Chlorine at the correct levels does NOT need ANY ‘backup’ from other algae prevention chemicals, it copes just fine all on its ownsum! Raising FC to shock level also destroys the chemicals that make up algae preventers… rendering them even more useless!

  • Jillian Wells Forbes

    I have an above ground pool but no way to vacuum to waste (pieces lost). I accidentally used a chemical to clear my pool that needs to vacuum to waste? How can I fix the mess I made?

  • Susann Michelle Newton

    I am desperate with my pool. I have not yet been able to swim in it this summer. I have dealt with 2 pool stores trying to get it clear and neither one can figure it out. I have used enzymes, clarifier, floc, filter aid, and they all have not helped. Even though the sand is only a year old, I wonder now if my filter is gummed up. I have a back up filter. Should I switch them? I would like to see the sand in the one I am using.

  • Matt Giovanisci

    If you can hook up a manually vacuum cleaner to your filter, just remove the drain plug on your filter. That would be like vacuuming to waste.

  • Matt Giovanisci

    If all your normal chemicals are correct, you should run your pool 24/7. If you have an inground pool, make sure your main drain at the bottom of your pool is sucking water into the filter. Add the recommended amount of clarifier (per the bottle) to your pool every day. Swim in it!!! Keep it running. It will clear! Again, as long as your pH, Alkalinity and chlorine are on the nose. It takes time and consistency, not band-aids and quick remedies.

  • Susann Michelle Newton

    I have an above ground pool that I run the filter 24/7. There isn’t anything that I think that I haven’t tried for my pool. I wondered if the floc that I could not vacuum out has clogged my filter. My pool will not clear. I think the levels are balanced now. The pool stores said floc but I could not see the bottom to vacuum the floc because it was not balanced. Help!!

  • Matt Giovanisci

    When you floc, you need to vacuum to waste, meaning the water you vacuum never touches the filter.

  • Dontay

    Susann… you would think the pool store guys would be experts in pool care but they are invariably and notoriously hopeless! Read all the posts on this site and you’ll see loads of complaints exactly the same as yours. You need to stop relying on the pool store, they will have you spending a fortune on chemicals. You know everything you have tried so far has not worked… right? You CAN clear your pool within a week, if you are prepared to go about it in the correct way and it is not complicated and it dosnt require you to be any sort of chemist to do it. Firstly you need to stop relying on pool store water tests, they are VERY inaccurate… so you need to purchase a test kit that you can use on site… because you will need to raise your FC to over shock level AND keep it there… you need to know exactly what the shock level for your water actually is and you need initially to be around to be able to do that testing every two to four hours… at least for a couple of days. You also need to stop using any sort of stabilsed tablets/pucks or powder based chlorine (they contain Cyanuric Acid (CYA) ) OR calcium based chlorine (Calcium Hypochlorite) also no more algaecides, flocks or clarifiers whilst shocking the pool. Use liquid chlorine (Sodium Hypochlrite) which your pool store should have in stock. IF you ARE prepared to have patience and do the testing yourself you can have water as clear as fresh drinking water without even the slightest hint of haze and that’s as sparkly as a diamond. Getting to that state means puchasing an FAS DPD test kit which is the ONLY kit that can accurately test FC and TC at shock level. ALL other types of DPD kits ‘bleach out’ the test reagents when chlorine is at shock level and give wildly differing and inacurate results. Of you use test strips, throw them away! Your pool store MAY stock their own branded version of a well known FAS DPD kit or they are available on-line. Simply Google FAS DPD test kits! Well known brands are Taylor or LaMotte. They test for all the usually things we need to know for pool care… including the most important ones when going to shock level… CYA and FC. Shock level is based on whatever your CYA currently is so you need to know both. FC shock level is 40% of your CYA. ( If CYA = 30 ppm then FC shock level is 12 ppm: CYA = 40 ppm- FC = 16 ppm: CYA = 50 ppm-FC = 20 ppm: CYA = 60 ppm-FC = 24 ppm: CYA 70 ppm-FC = 28 ppm.) The higher your CYA level actually is then the higher the shock level and the more chlorine you will need to buy in order reach shock level. If CYA is VERY high you may wish to dilute it by pumping away water and replacing it with fresh. Once shock level is reached or exceeded it needs to be kept there. In the initial stages FC will drop by several ppm’s within a couple of hours so you need to be around to test and constantly add more chlorine to maintain FC at or above shock level and KEEP doing that! Remove and clean any ladders or pool fittings that algae can hide behind including any underwater light fitting recesses which should be cleaned out. Keep the pump going 24/7 brush ALL surfaces at least twice a day, manually vacuum to filter once a day, backwash the filter once a day… topping up with fresh water as required and eventually you pool will become less cloudy, chlorine demand will start to slow requiring less dosing and eventually the water will become visually Crystal Clear which is the first ‘pass test’ it CAN and frequently DOES take several days! Do NOT let FC drop below shock level until that stage is reached. It WILL become clear… don’t give up… KEEP going! Then do an OCLT. Overnight Chlorine Loss Test. Once the water has not the slightest hint of haze left in it… turn of the pump after sundown and keep it off. Test and note FC (it should still be at or above shock level!). Test FC again before the sun is on the pool the next morning and before turning the pump on. If the FC overnight demand has been 1 ppm or less the water has passed the second test… so now test for CC. If the CC is 0.5 ppm or less you have passed all three requirements and you have successfully completed shocking the pool. Only when ALL three of those criterion have been met should you allow your FC level to return to normal over the following few days. Once it has done that use liquid chlorine as a routine and never again let your FC drop below 7.5% of your CYA. Do that and you’ll probably never have to shock your pool again.

  • Dan Kuzniewski

    My inground pool has a simple pump/filter operation. Just a three way valve so there is no way to vacuum to waste. The floc works great to settle everything at the bottom but then seems to get stirred back up when I vacuum. I have a DE filter. Any better method to vacuum? Just a pain to vacuum and then have to clear the cartridges and recharge with DE every time I need to floc or clear cloudy water.

  • Matt Giovanisci

    You can vacuum to waste by removing the backwash port on your filter.

  • Dan Kuzniewski

    but that still requires the filter to run and a bunch still gets back in the pool.

  • Matt Giovanisci

    Well it won’t go back in the pool if it’s being re-routed to the backwash port. But it does require you run the pump and you’ll lose a lot of water.

  • Dan Kuzniewski

    I suppose that’s the thing. There is no backwash port. Just an opening at the bottom of the filter that I can unscrew.

  • Matt Giovanisci

    How do you backwash your DE filter to fill it with new DE? That’s the same port sand filters use to vacuum to waste. The idea is your sucking the water directly out of your pool so that it doesn’t filter through the system.

  • Dan Kuzniewski

    I don’t backwash it because I have no way to. When my psi gets high I clean my cartridges and recharge with DE.

  • Dan Kuzniewski

    Here’s the setup

  • Matt Giovanisci

    I would try to block off the return with the gray shutoff valve (red handle) and open up the drain port. I would put a hose bib on there and run a backwash hose so you don’t flood the setup. That’s how I would vacuum to waste. That way you suck water into the system through your vacuum and right out the backwash hose so it never returns to the pool. Make sense?

  • Dontay

    Dan… if you don’t use flock then you won’t have the problem of continually having to clean and refresh your filter and you won’t have the problem of having no backwashing facility or need to think of various workarounds to overcome that drawback. A DE filter is one of the most efficient filters around so you need to question why you seem to continually suffer from cloudy water and eliminate the actual cause of It rather than continually firefighting the consequences of it. Backwashing or getting rid of waste water is obviously a problem for you but surly it is the cause of cloudy water which is at the root of the majority of your difficulties? At best flocks and clarifiers are only a temporary measure, they are not a permenat cure for the actual causes of cloudy water. If you keep your CYA/FC ratio correct, your PH in the 7.4-7.8 range and CH level below 350ppm… you wont have problems with cloudy water and you won’t need to use flock which are notoriously difficult to clear from filters.

  • praveen nadaraju

    I’m at wits end too. The pool is surrounded by trees. Just bought the house. Pretty old sand filter but works. Maybe its the old filter…no idea. Pioneer pools guided us after testing our water and still it is cloudy. Went back and got more chems from them “floc” etc. And still cloudy after following all the guidelines….3 weeks and counting. Vac’d out the sludge after the 1st liquid concentrate floc was added. Ran the filter for 24 hrs and still cloudy. The test strips show everything is at good levels. I did shock the pool twice now over this period.

  • Dontay

    Praven, if you read my post to Susaan on this thread 18 days ago you might gain a better understanding of why you haven’t been sucsefull. If you also follow that guidence you will have crystal clear water. Test strips are no more than toys, pool store testing methods are also completely unreliable and inaccurate and they will have you buying chemicals like there is going to be no tomorrow. Take the time it takes to purchase a proper water test kit and in the medium and long term you will save yourself hundreds $$$.

  • praveen nadaraju

    Thanks Dontay, So I got ripped off…..I knew that deer in a headlight look at Pioneer pools was a warning signal. Kidding aside. I read up. It is a little confusing but I will study more. First on the list a proper test kit. I will post results.

  • Dontay

    Praveen… your welcome and great that you want to learn how to get your water crystal clear, be in no doubt that you can and also KEEP it crystal clear. But don’t go too hard on the pool guys, any ‘rip off’ won’t be intentional. They invariably mean well but although the subject of CYA/FC ratios is something that has been known about since the mid 1970’s… and although there are now many thousands of pool owners who are more aware, who understand the importance of CYA/FC ratios AND the knowledge that a FAS DPD home test kit gives them… AND who have gained enormous economical benefits from both those understandings AND also have continuously crystal clear pool water as a result… it’s a subject which the chemical makers would prefer to be kept hidden in the shadows (for understandable commercial reasons) and the pool store folk are of course ‘educated’ by their suppliers reps and what is written on the back of their products. To most of them shockdosing pool water is something you should do as a routine preventative exercise. It’s not, it doesn’t ‘prevent’ anything. It’s a ‘cure’ for when your testing and chemical routines have slipped out for some reason and nothing more then that… and flocks do not and are NOT intended to… kill algae. Algae cells can be invisible until there are millions of them, cloudy water is invariably the first indication that there ARE millions of them and that first sign invariably isn’t due to an efficient filter that can’t handle very small physical particles… it’s algae! You actually need very little chlorine in the water as an anti-bacterial agent and so keep CC under control in an outside pool… (that becomes more important in an indoor pool) but you DO need to keep FC at correct minimum levels to protect against algae in an outside pool. If you KEEP the correct levels, algae spores will not invade your water but once you let them in there is only one way to kill them. A quick basic chemistry background to get you going: When you stick chlorine in the water a percentage is instantly converted to Hypochlorous Acid (HOCL).Thats the disinfecting agent in chlorine that we call Free Chlorine (FC) The percentage that’s created is dependant on the PH level. HOCL is a highly unstable molecule which dissipates rapidly in the presence of sunlight. Proper stabilisation of HOCL with CYA seriously slows the rate of dissipation by the sun without appreciably sacrificing oxidisation & disinfection activity. HOCL reacts with substances other than water to produce ammonia which in turn produces chloromines, this occurs in several stages with HOCL (FC) consumed at each stage. With FC kept at correct levels and the water exposed to sunlight for the equivalent of 2 days a week CC rarely becomes a problem… and UV sunlight is a very effective and free way to keep them under control! Anywhere between zero and 0.5 ppm is fine. ONLY when CC has got above 0.5 ppm do you have to shock to get them down. THAT it easily and quickly done… usually within a day or so. Algae is a different matter and unfotunately the most common and persistent problem. HOCL also easily dissociates into an ionised hypochlorite state called Hypochlorite Ion (OCI). The balance between HOCL and OCI is effected by PH levels. The higher the PH the less HOCL is present… and so FC is less effective. At a 7.2 PH roughly 66% is of chlorine is effective FC (HOCL) At PH 7.8… around 33% is effective FC ( but that’s fine!) if above 7.8 then immediatly get it down! Now then…. CYA shields a percentage of HOCL from the sun by moderating it’s strength and also by ‘binding’ a percentage of it and holding it in reserve… that ‘held back’ proportion is released in direct proportion to the the amount of ‘unbound’ FC as it is consumed. IF you chlorinate to 3ppm in an outside un-stabilised pool… then in noonday sun that 3 ppm of FC a will be gone in an hour and a half… the vast majority of it taken out by the sun! So it’s vital to have CYA in an outside pool but FC is ALL about percentages! The higher the CYA level then the higher your FC level has to be in order to allow for that ‘bound up’ FC percentage. The hotter the sun the more intense the UV and the more rapidly the ‘unbound’ FC gets eaten up… so the more rapidly CYA ‘bound up’ FC also gets released and eaten up! SO… the hotter your normal ambient climate the higher you should have CYA to protect against loss and therefore the higher your FC level should be! It’s ALL about percentages! The FAS DPD test kit shows the total amount of FC… unbound and bound. Algae spores take a long time to die and if you leave even a couple left alive after shocking the water they will multiply again and you will be starting all over again within a 2/3 weeks. Shocking or shockdosing are not the correct terms to use when killing algae and as lemmon111 very correctly pointed out in his recent post out there is no such thing as product called shock! There are only various chlorine products that will raise FC to shock levels and each add other things to the water, some that you don’t want! SLAMMING the water is a far better term to describe the proceedure and prevents confusion. You SLAM the water by raising your FC to ‘SHOCK LEVEL’ and you keep it SLAMMED until you meet the three ‘endgame’ criteria. It CAN take several days! BUT it WORKS! If your CYA is 30pppm then your FC SLAM level is 12ppm. If you have algae spores take the initial SLAM level to 16ppm and test again 2/4 hours later and you will invariably find FC has dropped to near your target slam level and it will keep dropping! Thats WHY you need to be available to test the water AND keep it to OR above that SLAM level. FC gets consumed by the the act of consuming… it will start ‘consuming’ as soon as its hits the water! FC can drop like a stone in an algae contaminated pool at slam levels! But that’s your PROOF that the SLAM is working… FC is rapidly being ‘eaten’ up. The CYA test (unlike the other parameters) is a water turbidity test. Even eliminating operator errors all turbidity tests will only give a ‘thereabouts’ reading with +|/- accuracy of around 10 ppm so allow for that when slamming and allow for it when things get back to normal. Minimum FC is 7.5% of CYA so 7.5% of CYA at 30ppm gives FC at a minimum of 2 ppm. (CYA should never in anycase be below 30ppm and FC should never in anycase be below 2ppm!!!) But to allow for the +/- accuracy of turbidity simply keep your minimum to another 1 ppm higher than 7.5 % and as many others have found you’ll probably never have cloudy water or have to slam the pool again!

  • Donna Wisswell

    I have so much pollen in my pool that my water is green. Shocking doesnt help & vacuuming just pushes it around. I have an intex 18×36 above ground pool. HELP

  • Matt Giovanisci

    You have to keep skimming the pollen out.

  • Dontay

    Donna… is it pollen? Or is it algea? Pollen usually settles on the bottom but doesn’t normally turn the water green. It’s algea that does that. Is the water green but clear so you can see the bottom? What kit do you use to test the water? What are your test results? Shocking won’t clear pollen! Shocking kills algea. Algea is alive, pollen is not! If you decide its algae read up on the guidence I gave to susann and praveen on this thread. If the water is emerald and yet completely clear then it’s probably high metal content and you need a ‘metal out’ product.

  • Donna Wisswell

    Its pollen. the more i sweep the more it just finds another place to settle. Should i try the “floc”? Nothing else i do clears up the bottom. The water is clear & the water balances are good.

  • Dontay

    Hi Donna… If it’s all on the bottom flock won’t work since that’s what flock does… binds it up particles and dumps it on the bottom so you can vacuum it up. Flock can have its uses but also notorious for clogging up filters. Manually vacuuming the pollen dust back to the filter VERY slowly and carefully as you can, so you disturb the pollen dust as little as possible should clear anything gathered on the bottom. It may take several goes where you have to wait for it to settle again but there is no reason why you shoudnt get there! Robot type vacuums disturb dust more than sucking it up! As you have found, brushing also just moves it around. Chlorine won’t make pollen magically disappear or become invisible, that isn’t its function, only vacuuming it into the filter then eventually backwashing will do that. Only backwash when there is a need to, when PSI gets around 25% higher than usual is best…. to much backwashing isn’t a good idea and can cause more problems. Also might be a good idea… if pollen is a continual problem… to insert a skimmer sock to catch as much green dust as possible before it reaches the filter when you vacuum. Filter socks are an inexpensive item and are usually available in pool stores or on line. You can wash them out when done and reuse when necessary.

  • praveen nadaraju

    Pool is spotless!!!!!

  • Dontay

    Hey praveen, well done buddy and great you got it that way. The trick now is to keep it like that. The CYA disappearing dot turbidity test has a margin of error of around plus or minus 10 ppm and even that can be increased by slight operator errors. The top of the sample water level in the test has a slight curve. Ensure that the bottom of the curve is exactly in line with the level mark, slightly above or below that level can increase the MoE by another 5%. That curve effect applies to ALL tests in the kit. FC ABSOLUTE minimum level should be 7.5 % of whatever your CYA is. To allow for that turbidity test MoE it’s safer to set your FC absolute minimum at another 1 ppm higher than 7.5 % and operate your pool with that built in allowance. Now you have a proper test kit you should get to know your pool and learn what YOUR pool FC requirments and FC demand actually is as opposed to someone else’s pool. Easily done by testing in the morning on a sunny day and then again at sundown so you can determine what the demand has been during the day as well as overnight. Don’t be afraid of chlorine… it’s in our drinking water… some states have 3ppm! It’s chloromines (combined chlorine) that is dangerous. Another myth you can forget now you have a healthy pool is the one that says you have to turn over your water twice a day or for at least 8 hours. No you don’t! Filters filter the water, nothing else! They do not sanitise it! If your water is crystal clear after one turn over period then there is no need to filter it again. Know how many gallons per hour your pump handles, know your approx volume of water and work it out from there. You may find 4 hours is fine… or even less. You can even split the ciculation time between morning and evening if you want too, some folk prefer doing that to keep the water mixed. Do something like that and you cut your energy bills in half and double the life of your equipment. Best of luck and thanks for reporting back.

  • jimwill

    I backwashed my D.E. filter yesterday (first time for me), but I forgot to turn the pump on before adding the D.E. powder to the skimmer. So powder entered the pool from the skimmer.

    Now the water is cloudy. Will the issue fix itself as the water is filtered?

  • Dontay

    jimwill, yes it will. It’s not a problem and won’t cause any harm. The ways some folk end up with DE in the pool are many and varied! Keep the pump running on filtration and it will make its way back to the filter and the water will gradually come clear again. If you have an auto vacumm, run that frequently also… or if not very slowly and carefully manually vacumm a couple of times a day to get it off the bottom. It pays to keep your eye on the filter pressure whilst this is going on. The normal routine is to only backwash filters when the gauge indicates psi around 25% above normal clean filter pressure. You may or may not find you have to backwash again when your done but other than experiencing cloudy water… DE in the pool is not a major problem.

  • jimwill

    Thanks, Dontay. The DE is settling on the bottom mostly, so I ordered a vacuum head today so I can clean it out.

  • Michael

    I have a 25,00 gal inground pool turned green put 9 lb chlorine cleaned to waste added 6lb cleaned to waste next day 6lb clean to waste now day 4 checked chlorine after vacuum and only had a 1.5 now what to sdo still bluish green been scrubing every day should I use floocunt

  • Dontay

    Michael, flocks don’t kill algea. You have algea. The only thing that will kill algea is chlorine. You will also not successfully kill it with the way you are going about adding chlorine to the pool. You should only be adding chlorine using specific FC test measurements… not weight, and you need to be able to take those measurements yourself. The volume of water in your pool is to large degree irrelevant. In the initial stages you need to be available at least every 2-4 hours in order to take those test measurements. You have to raise your FC level to chlorine’s oxidisation point which is at least 40% above whatever your CYA level currently is… and you have to KEEP it at or above that level until your water becomes crystal clear. In the initial stages (at least for a couple of days… maybe longer)… you will find your FC level will rapidly drop and you need to there to test and continually add chlorine in order to keep it above your specific shock level (40% of CYA). It can take several days. You should not under any circumstances rely on pool store test measurements OR inferior and inaccurate home test kits, or you will spend a fortune on chemicals and still end up with cloudy or green water. Neither do you need to panic! Purchase a FAS DPD test kit. Available on-line (simply Google FAS DPD test kits if not available in your pool store)… well known kits are made by LaMotte and Taylor Industries. They test for ALL the normal pool water parameters They are the most accurate home testing kits on the market and over time will save you hundreds of $$$. You need one of these kits in order to accuratly ensure you get to… and stay above… that all important chlorine oxidisation point. ALL other test kits can be seriously inaccurate when the FC levels are high levels above 5ppm due to a ‘bleaching out’ effect. Once you are armed with a ‘proper’ test kit you can start to get back to clear water. You also need to be aware that there are several different products that are called ‘chlorine’. Most of them contain additional substances that you may not want in your pool water. Do not use any powder type chlorine product which is labled ‘stabilised’… it contains CYA OR calcium based chlorine Cyanuric acid is required but only at suffcient levels to restrict to suns ability to burn chlorine from the pool. Calcium levels have to stay below 350ppm or will get further problems. When shocking your pool there is only one product which will not cause you any other problems… and that is liquid chlorine known as ‘Sodium Hypoclorite’. Basically it’s liquid unscented bleach and the only other substance it contains apart from water is a small amount of harmless salt. You pool store should sell it. Once you get to a visually totally crystal clear water state you need then to pass an OCULT test. Overnight Chlorine Loss Test. You have not completed completed shocking the water until three criterion are met. 1) crystal clear water. 2) Test FC when the sun has gone off the pool and note the result, turn off the circulation and do not add any more chlorine. Test FC again early the following morning before the pool is in sunshine. If FC overnight loss is one ppm or less you have passed the second requirement. 3) Test CC (Combined Chlorine) if CC is 0.5ppm or less you have passed the the third requirement. You can now allow your FC level to return to normal. ‘Normal’ means keeping your absolute minimum FC level no less than at least 7.5% of your CYA level… plus one ppm more!. If you follow those procedures you will not have to shock you pool ever again. However before you start the proceedure you should remove any fixings that algea can hide behind and leave them removed until OCULT is passed. Typical example are ladder fixings, underwater light lenses and vynal liner recesses below the coping. All should be removed and thoroughly cleaned. Unlike advise given elsewhere you should realise that shocking the pool is not a preventative exercise that should be done to some abitary timescale… it’s a cure… but if the correct proceedure is not carried out then you will have no option but to keep shocking the pool on a regular basis because you will not have cured the problem… you will have left some algea spores alive… and they will slowly begin to multiply once again! Fine if you wish to keep spending money! Minimum CYA is 30ppm. Minimum FC is 2ppm regardless of anything else. Beyond that… routine ABSOLUTE minimum FC is 7.5% of CYA… PLUS (to be on the safe side) another 1ppm. It is VERY important that PH should be BELOW 7.8 before starting shock proceedure.

  • Once you go Bear, Arnie Grape

    Great Article. Thanks.

  • Shirish

    Help please! I have shocked the pool, treated with metal-free, algaecide and shocked again! I brushed the floor and vacuumed. I also changed filters yesterday. It’s still cloudy! By the way, chlorine level is way high( Dark orange). What do I do now?

  • Dontay

    Hi Shirish What should you do now? Well a good place to start is to have a read through the advice given firstly to Susaan and then also praveen on this thread, so you know where you are going wrong. From the sound of it… your using test strips… what does “dark orange” mean? what does “way high” mean? The only way to ‘shock’ a pool successfully is to know what exactly your FC shock point actually is in ppm figures… ( it could be 12ppm… it could 20ppm… it could be any level) but you then have to keep the pool above that level with circulation on 24/7 until the water comes crystal clear. It can and does take several days. If you don’t do it properly the problem will return very quickly. Your shock point is determined by whatever your CYA (cyanuric acid) level actually is. FC oxidisation (‘shock’ level) occurs at 40% above whatever your CYA figure is. To get those figures you need an FAS DPD test kit. Read the advice below, buy a proper FAS DPD test kit, either in store or online and use only liquid chlorine (Sodium Hypochlorite)… and don’t bother with algaecides.

  • Jeanne Randall

    I killed the algae….. put in the floc so I could vacuum to waste. I used too much floc….. the pool water looks crystal clear, but I have white “soap-like scum” floating on top. I turn off the pump, it all settles, I vacuum to waste, turn the pump back to filter and within an hour I have the white stuff back on the top of the water. Will it go away on it’s own (my pump runs 24/7) or do I need to add a different chemical to neutralize this mess?

  • Dontay

    Jeans… to start at the beginning, if your filter is in good order then regardless of the actual type of filter you have there should never be any reason to use flocks. IF you DO then you should never, EVER vacuum it back to the filter… always vacuum it away to waste. Filters get clogged up by flocks and even backwashing the filter can fail to clear it. The first thing to do is check your filter pressure gauge. The rule is that when pressure rises more than 25% above clean water pressure then that is the time to backwash. Flocks do not kill algae. Chlorine is the only chemical that actually kills algae… but even then… only provided you use the correct method. There is no chemical that will magically remove physical matter from water. Not even chlorine does that… it’s the filter running 24/7 that does that… and a normally efficient filter does not need any help from flocks. Ok… that’s the background… I suggest you now try manually (not robot types) vacuuming whatever that white scum is… to waste! The problem with that is you will lose water very quickly. Before starting top your water level up as high as you can possibly go… keeping the hose pipe turned on… be super organised and ready to go with your vacuum. It may need several goes at it over a long period but hopefully you will start to see an improvement. You will lose water faster than your hose can replace it so keep your eyes on the water level and stop everything to top up again when required. If your sucsseful with that.. the next step is get your water level back up as high as it will go again and only now should you backwash and rinse the filter. If your filter gauge shows normal clean water pressure after that… then you will have succeeded. However you may find that you will have to change your filtration media if you don’t get back to clean water pressure. If you have a sand filter than change the sand… if it’s a cartridge type then change the cartridge. Best of luck!

  • Jeanne Randall

    Thanks…… I will keep sucking that gunk off the top of the water……. I was y hoping that there was a quick fix…. but as this will work…. slow and steady it’s OK!!

  • Dontay

    Best of luck Jeanne, be aware also that if you have a standard multi-port valve… you will likely have a circulation position in addition to the filtration position. ‘Circulation’ keeps the water going through the system as normal but simply by-passes the filter. It can come in handy if there are any delays but need to keep water moving around for sanitation reasons without depositing gunk that maybe already in the filter back into the pool. Another thought is skimmer socks. Some pool stores stock them or they are available on line. eBay is good source. They simply line the skimmer/leaf basket and help stop a lot of really small particles getting back to the filter. I’m not sure why you have this stuff floating around on the surface… flocks are a binding agent and are supposed to bind small physicals particles together to make them bigger… and sink them to the bottom and make it easier to vacuum out. It’s because it IS a binding agent that you shouldn’t send it through the filter…. it can bind your filter media up… and you def don’t want that! As stated though… filter media in reasonably good condition does the job just fine without help from flock. There does seem to be a lot of confusion over what a filter actually does… it doesn’t disinfect or sanitise… it merely removes physical matter, whereas chlorine does NOT remove physical matter. Chlorine disinfects and sanitises and will stop algae invading the water providing you keep FC above 7.5% of CYA. At very high levels it also kills algae if you ever let in. Then you remove the dead stuff via the filter. No need for flocks.

  • Shirish


    Thanks for the feedback. I got side tracked for few days. In any case, my pool water is still cloudy! The total Chlorine is 13.6 ppm, however Free chlorine is zero. Cyanuric Acid is 110 ppm. Reading all your advise, it appears that CYA is very high. Should I empty some water first before I shock it with Sodium Hypochlorite liquid? How much do I put in to get the FC/CYA more than 7.5? Store people are not very helpful. Thanks in advance.

  • Dontay

    Hey Shirsish… well done for identifying your problem! Yes, your quite correct, your CYA is far too high and it would be pointless sticking any more chlorine in at this stage because it would be totaly ineffective. Unfortunately there is no chemical that lowers CYA levels, it can only be done by draining water away and replacing it with fresh. CYA is a manufactured product, it doesn’t appear naturally and the working guideline is:- if you lower the water level by 50% and top back up with fresh water then your CYA level will also be reduced by 50%. CYA is vital to have in an outside pool in order to restrict the suns ability via its UV (ultra violet) light to burn chlorine out of the water… but you don’t need too much of it! That’s the problem with using stabilised chlorine powder or stabilised tablets/pucks… easy and very convenient… but CYA levels just keep on building up! The downside to CYA is that the higher the level the more it limits chlorines ability to protect and disinfect the pool and therefore corespondingly higher levels of chlorine are required to overcome that restriction. Eventually you get to a condition known as ‘Chlorine Block’ … chlorine stops working…. which is where you probably are now! CYA should never be less than 30ppm even in cold climates. 30ppm is also fine in normally temperate climates that rarely exceed 30C. In moderately warm climates where air temps regularly get to around 35C… CYA levels between 35/40ppm are normally sufficient. In increasingly hotter climates 40/50ppm of CYA will be needed to shield chlorine from the very strong UV light and folk who live in those climates simply accept they need higher levels of FC. So your aim and ‘end point’ in the CYA stakes depends on YOUR normal summer air temperatures. The 7.5% FC figure is the absolute ROUTINE minimum needed to PROTECT against algae invasion. Because even the best CYA test kits known as the ‘Disappearing Dot’ test has a plus or minus margin of error i advocate exceeding that minimum 7.5% by another 1ppm simply to allow for the MoE and to ensure you stay on the safe side of it. VERY importantly tho… FC at 7.5% of CYA only PROTECTS against algae setting up in your pool… if you fall below that and you let it get set up giving you cloudy which is what you have now (and eventually green water)… that 7.5% is totally inadequate…. it’s nowhere near enough to actually kill it! Unfortunately the percentage of FC to CYA required to take chlorine to its oxidisation point (shock point) where a chemical reaction occurs and chlorine starts to kill algae and clear your water…. is 40%. EXAMPLE: CYA at 30ppm requires FC at 40% of that = a minimum 12ppm. You can see therefore that with CYA as it is at your 110ppm figure…. raising FC to a minimum of 40% AND having to keep it over that level fror several days till your water comes clear would require an awful lot of chlorine! So yes,, your gonna have to get that CYA way down before you do anything else. If you have a liner pool please don’t attempt to do it all in one go.. you risk ruining the liner… no more than a couple of feet of water should be emptied out of a liner pool at any one time… replace with fresh… circulate for half an hour to mix it up… then remove some more. Because you will have to do this I suggest you keep going and aim to replace the majority of your water and get your CYA well down…. even as low as 20ppm in this instance will be good because the lower the CYA is… the less chlorine your gonna need to buy to get to a 40% shock point and start getting back to crystal clear water. With CYA at 20ppm your FC shock level is only 8ppm. Water is expensive but generally not as expensive as chlorine! You can always buy a tub of CYA to bring It back up to suit whatever your climate is afterwards. Liquid chlorine (Sodium Hypo) is simply bleach but remember it’s also lots stronger than normal household bleach so be careful when pouring it in. Even the smallest spots from slashes will immediately bleach your clothes! Pour it into the inlet currents and it will mix your water within 30 minutes. The strength is usually indicated on the container and there are different strengths available… just buy the strongest available to you locally. You seem to have only cloudy water rather than green water and if you get CYA right down to start with you may not need to buy too much. How much do you actually need? Much depends on the level of contamination and how long you have to stay above shock level… in conjunction with your volume of water… but one litre of Sodium Hypo with an 7.5/8% strength… will raise FC by around 1ppm in approx 13,000 US galls of water. Also remember FC levels only go one way… downwards! It is itself gobbled up by the job it does when gobbling up the nasties! The point is, with a contaminated pool it’s good to well exceed that 40% of CYA which is only a minimum figure because it gets gobbled up very quickly indeed… and it’s vital to KEEP it above that minimum till you get to totaly clear water. Shirish… I hope that helps to get you on the way… no need to panic… all pool probs are solvable, let us know how you get on and please don’t hesitate to get back to me if there is anything I say or have said that seems confusing.

  • Rose

    We had cloudy pool too and finally after doing everything we could spending a fortune we flocked it and it did the trick and pool places will not tell you that till you spend Money on every thing else

  • Rose

    Flock it bye a floccunt and that will do the job

  • Rose

    Flocking is only thing that cleared our cloudy pool and we might need to do it again but think we will see how the one time will do. How is your pool doing now? We have a good pump and filter and nothing was working so I think flocking was best thing after spending money on clorine and everything else in the book nothing helped. Good luck with your pool now

  • Rose

    If you get clorine low and still cloudy you might want to flock it and really wasn’t that much trouble honestly just like vacuuming your pool and does the trick good luck

  • Shirish

    Thanks, Rose! I put some clarifier and put new filter cartridges. It cleared up in 2 days. Needed some patience on my part. Water is crystal clear now.

  • Sunny

    I have read and reread this whole thread maybe three times. Part of why I’m having to reread is that my situation, although similar seems to have unique differences. The biggest difference is that our school is here in China and I do not know exactly what the makeup of the chemicals here. The chlorine is in the form of tablets, both small ones and larger ones, and the acid is a form of powder/small crystals. So I finally decided that posting will probably be the best things and getting feedback from you the experts. Recently, our small school moved into a facility that has an indoor pool. The water was quite clear but never really used. The pool pump runs 24/7 and it’s more because once you turn the pump off it is very difficult to get it working again. There seems to be a leak somewhere that allows for air to get into the system but if left on keeps working fine. When we were being shown how to use operate the pumps, there was a mistake and the pool was half emptied. I share this to mention that the water is basically new. Anyway, as the weather got warmer, we purchased a solar cover, the temperature was rising, and when I tested the water with a “Swimming Season 3-way Pool Test Kit,” it showed that the water had a high PH and a low chlorine level. We didn’t do anything to the pool and used it one day. Two days later it showed that the PH was way too high so we added the acid as one of our staff grew up with an outdoor and felt he knew what needed to be done. We covered up the pool and then two days later the pool was very cloudy. We tried adding more chlorine and there was a slight improvement but the water was not crystal clear. When the test showed that PH was still too high, I added more acid. I have since purchased another test kit “5-way Test Kit For Pool & Spa,” but it does not have a CYA test nor a FC and TC test that I know of. I have looked for other test kits but I have not been successful. I have been able to identify where I can buy the Sodium Hypoclorite but for now I will have to use the tablets available to me. I am hoping to get the water ready and clear for some students to use the pool this coming Monday. The plan is to get the PH to around 7.2 so that the chlorine will be more effective. In the absence of the measurements of CYA, FC, and TC, I was thinking to just put is a lot of the chlorine to “shock” the pool and get rid of the cloudyness. Any and all thoughts are greatly appreciated. As for the solar cover, is this adding to the cloudyness? Am I on the right track? Am I way off? I will do my best to get the right test kit and chemicals to maintain the pool. Should I give up on trying to have the pool ready for Monday’s PE class? Thank you all in advance.

  • Dontay

    Hi Sunny, as far as your pump is concerned it is quite normal for any leak to show itself once it’s off rather than when it’s running, the pressure relaxes and air can get in. In the vast majority of cases that happens on the suction side of pump rather than on the outgoing side. It’s usually above ground and occurs around one of the pipe joints near the pump which may have loosened over time. One way of tracking it down is to turn the pump off and try (at exactly the same time) to observe if there is a sudden tiny spurt of water around one of the joints. Chlorine tablets DO come in two sizes… that’s quiet normal and both have the same chemical make up. These tablets are stabilised which is the generic term for CYA. Acid usually known as dry acid is as you have describe, small flaky crystals… that need to be diluted in well stirred a bucket of warm/hot water before slowly pouring it around the perimeter of the pool. It’s not strictly necessary to have cya in an indoor pool but it is good to have some. CYA works in two ways… It ‘binds up’ a percentage of chlorine and restricts the suns ability to lift it out of the water in an outdoor pool. The other way… it moderates the strength of chlorine. Most indoor pools are over chlorinated simply because they don’t have any cya moderating the strength of whatever ppm’s they normally keep to. But the same problems of having TOO high a level of cya arise. CYA increasingly restricts chlorines ability to sanitise the water. The higher the cya then the higher the the levels of chlorine that are required. The PH scale run from one (acid) to fourteen (base) Seven is neutral. There is a hundred point difference between each point of the PH scale which can make it difficult to alter. ((7.2 is one hundred times more acidic than 7.3) Human membranes, eyes, ears, nose, throat etc, are happier if the PH is on the alkaline side of neutral. For this reason it’s recommended that pool water should ideally be between 7.4 and 7.8. 7.6 is ideal because that gives some leeway for it to go up or down. Your correct that 7.2 makes chlorine more effective but it should only be brought down to that level to facilitate shockdose procedures. 7.2 IS safe for bathers but it’s not ideal and eye irritation can soon become noticeable. 7.8 is actually fine for chlorines effectiveness as a sanitiser but above that figure it rapidly slows down that effectiveness and that leads to chloramines (Combined Chlorine) rising. High Chloramines can and DO give cloudy water!!! Chloramines are basically dead material…. a combination of dead bacteria and ‘used up’ chlorine… it’s high CC which is normally responsible for strong chlorine smells and eye irritation or cloudy vision in public pools. For health reasons it’s vial that CC should not rise above 5ppm and ideally be under 2ppm in any pool. In an outdoor pool where chloramines are easily burnt out of the water by exposure to sunlight any reading above 0.5 ppm is indicative of the start of water problems. It’s not possible to test directly for CC. Therefore we test for FC and then TC (TOTAL chlorine). Subtract FC from the TC figure and what you are left with is CC. So your problem with cloudy water could be due to PH being over 7.8 giving rise to a lack of chlorines effectiveness to sanitise the water and keep CC under control. One of the reasons for PH levels being difficult to lower is due to having high TA (Total Alkalinity) TA which is a measurement of various carbonates s harmless in itself but ‘buffers’ the water against swings in PH values. If TA is very high it becomes very difficult to lower PH (when required) because the chemical used to lower PF gets ‘eaten up’ by the alkalinity of the water. This can increasingly occur at indeterminate TA levels above 130ppm. Ideally TA should be in the 80 to 120ppm range although if PH seems to stay reasonably stable in the 7.4 to 7.8 range there is no need to worry… some pools live quite happily well outside the recommended TA range. If your desperate for the pool to be available for use on Monday I suggest you don’t worry too much about PH for the time being because lowering PH is time consuming and really should only be re-tested 24-36 hours after action has been taken… and only then make further adjustments if required… it can take a week it two! For your purposes the most important thing is to ensure that CC is below 5ppm… if it is and you have reasonable FC levels then your students will most likely be safe! If you just put loads of chlorine in the water to shockdose levels.. in an indoor pool you are actually at risk that the water will not be back down to safe FC bathing levels by Monday.

  • Jon Rossiter

    I have a 24′ round 54″ deep above ground pool with a cartridge filter with chlorine. The first 3 yrs I owned it we had no problems with water quality. Last year I opened it as normal but after balancing the water was very cloudy (could not see more than 8-10″ below surface). I spent the summer and lots of money at the pool store every week. There response was dump this in and come back next week to retest. After many weeks of this and not getting in the pool once, I went to another pool store. By this time it was almost September so we decided to close it an start fresh in the spring. Now it’s spring, leaves vacuumed, start up kit used per directions. Balanced chemicals as best I could with test strips. Filter running non stop 24/7. TC at about 2.0, pH 7.2, TA 90. Still just as cloudy. Took water sample to pool store and they said was just a little low on pH (7.0). Added some pH + and waited a day before retesting. My numbers showed 7.4. Store agreed all other numbers were at ideal levels. Waited for a week and no change in cloudiness. Store guy came out and put a gallon of Pool First Aid which he said was a good clarifier for cartridge filters. Waited 24 then 48 hrs and no change. Tried floc next. Run pump for 2-3 hrs to circulate then turned off for 24 then 48 hrs. No change but manual vacuumed to waste anyway. Pool store guy is out of ideas. Said in 30 years never saw a pool not respond like this.

    Saw a comment on here about leaving the manual vacuum running at bottom of pool to get the cloudier water into the filter (remember I can only see down 8-10″ from surface). If this does not help I’m lost what to try next. Should I drain the pool (partially at least if not mostly)? Always heard never to drain an above ground pool but just don’t know what to do next. Any ideas????


  • Dontay

    Jon your TA is fine, TA should be 80-120ppm but even outside that range can be fine… and your PH is fine if it’s now 7.4. PH should be in the 7.4-7.8 range. The 1-3 ppm rule for FC doesn’t apply to outside pools, doesn’t matter if above or below ground. The FC levels in an outside pool are determined by your CYA level. Minimum FC is 7.5 % of whatever your CYA level is. If that percentage is not correct in your pool and you have high CYA levels then your FC of around 2 ppm maybe far to low. If that should be the case then I would suspect the reason for your cloudy water could be high chloramines. (High COMBINED CHLORINE) You have not mentioned what your TC (TOTAL CHLORINE) is or what your CC levels are. Also If you have been using any form of stabilised chlorine, tablets/pucks or powder then your CYA levels will have kept on rising. High CYA can only be lowered by dilution. However in order to determine EXACTLY what is coursing the problem… you need to get provably accurate information from your water. Test strips, no matter if they have a digital read out analyser… or if you manually compare color shading with a chart or in a comparitor… do not do that. Test strips are a waste of time and you really need to get away from using them. In the vast majority of cases neither are pool store testing machines accurate. Go to several different stores with the same sample of water and you will get several different results! The reason for that is two fold. Their machines are very rarely re-calibrated which ideally should be done once a month minimum… you’ll be lucky if they get their equipment re-calibrated once a season! Also the tablet regents they use do not give accurate information in even in a newly calibrated machine when FC is above 5ppm. The mimimum test kit any outside residential pool owner should have is a FAS DPD kit which are readily available on-line. Taylor Industries and LaMotte are the most commonly used ones. They both make fully comprehensive kits but LAMotte also make a separate FAS DPD kit just for FC and TC, they also make a separate kit just for CYA. Those are the minimum you need to get accurate information from your pool water. If you have to drain due to high CYA levels then do it in small stages… not all at once. The working rule is: drain 50% of water, replace with fresh and you also lower CYA levels by 50%. Anyone with CYA levels above 60ppm will find it more economical to dilute CYA before shock-dosing.
    This is the correlation chart showing the relationship/ratios of CYA & FC & Shockdose Breakpoint (minimum FC is 7.5% of CYA and FC shockdose points are minimum 40% of CYA)

    CYA P.P.M. Min. FC P.P.M Max. FC P.P.M. Min. Shockdose PPM
    20 2.0 3 10
    30 2.2 4 12
    40 3.0 5 16
    50 4.0 6 20
    60 5.0 7 24
    70 5.0 8 28
    80 6.0 9 31
    90 7.0 10 35

    Your routine FC should be kept as close to MAX figure as possible (the MIN figures are absolute minimum routine figures)

  • Sunny

    Thank you Dontay!

    I don’t have the appropriate tests right now to figure out CC so I will do my best to maintain the Chlorine level between 1-3. As for the cloudyness, is it ok for students to spend about an hour in the water?

  • Sunny

    Is this the right test kit?

  • Dontay

    Sunny… it depends on the level of chloramines. They are the ‘tell tale’ on If the pool is disinfected to a safe level. they MUST be under 5.0ppm. The control of Chloramines is a vital requirement in any indoor pool… and staff take constant hourly samples in public indoor pools to ensure there is no danger to bathers. They are not normally a problem in outdoor pools where they are burnt off by sunlight… and blown away by wind. In the atmosphere of an indoor pool where there is no wind or direct sunlight they have to be strictly monitored and controlled. Chloramines contaminate the top couple on inches of water and also float in around a couple of inches of the air above the surface. High chloramines are far more hazardous to human health than an over chlorinated pool and can cause long term very serious ill health issues. FC safe bathing levels are between 0.5ppm and 8.0ppm. Reasonably safe chloramine levels are 2ppm, ideally they should be below 1ppm… and VERY dangerous above 5.0ppm. If you are not in a position to ensure safe levels of Chloramines then you shouldn’t allow the pool to be used until you are… sorry!

  • Sunny

    Understood. Is the test kit above the right one? Would just a regular DPD test kit do the trick, meaning will it tell me the amount of Chloramines?

  • Dontay

    Sunny, there are many different types of kits available, they all go by different names, and some only test for very basic pool water parameters. The test chemicals used in any form of kit are called regents… they can be in the form of impregnated sponge pads on test strips, tablets, liquids in droplet bottles… and powder form. DPD is just the name of the regant used to test for FC and that can also take all those different forms. Test regents have a shelf life… a ‘use by date’… normally 2 years maximum and even then have to stored away from bright lights in a reasonably cool dark place. There is only one kit that will give accurate information and that is an FAS DPD test kit… the DPD is in a powder form in these kits. It’s a two part The DPD part is a small tub of powder in which you dispense one gramm of DPD powder with a one gramm provided ‘spoon… into the water sample which then changes to the familiar pink FC colour. The FAS part of the kit is a liquid called Titrant in a small droplet bottle. You dispense drops of Titrant into the test sample water, counting each drops as do so, you carry on doing that until the water sample becomes completely crystal clear. Multipling the number of drops by 0.5 gives you the FC figure. ( i.e. If 8 drops are needed to give clear water then 4ppm is your FC. If nine drops then 4.5ppm is your FC ppm. In order to get the CC info you add 1 tablet to the mix and shake until it’s dissolved… then add Titrant again as before until the water turns back to pink. One drop indicates 0.5ppm. Two drops indicate 1ppm. If it takes more drops to change the colour it indicates you have a problem!!! There is no mistaking an FAS DPD test kit. Regardless of manufacturer… it’s still called an FAS DPD test kit. The most well known manufactures are two American companies, Taylor Industries and LaMotte. They both make fully comprehensive kits that test for all the usual pool water parameters… TA, PH, CC, (chloramines) FC, CYA as well as CH (calcium hardness). LaMotte also make two stand alone test kits… one is a CYA only test and the other is an FAS DPD kit which tests for FC and TC only. The CYA test which unlike all other parameters is a water turbity test… it’s generically known as a ‘disappearing dot’ test which is the most accurate way of testing for CYA. Those two ‘stand alone’ kits will give you the accurate info you need most to resolve your problem. The 3 or 5 way pool and spar kits you mentioned will NOT be FAS DPD test kits, they will be either test strips or tablets that you use in one way or another to compare different colour shades. Test strips in particular are only toys, they do not have a use by date on them, they could well have been in existence for years under bright, warm shop shelves. Tablet regants IF in date, give reasonably accurate FC and TC readings up to around 4-5ppm. Over that they become increasingly very inaccurate. Pool stores may test your water sample but the problem with that is they use tablets which again have been stored in a brightly lit warm shop shelves… and the anayliser they use have invariably never been re-calibrated… professional water test analysers, again are a colour spectrum test and should be re-calibrated one a month. Given your cloudy water problem… which could well be down to unsafe combined chlorine levels, I think the only responsible answer, with the safety of your students in mind… is to say don’t go in until you know for certain that it’s safe.

  • Jon Rossiter

    Thanks for the detailed response! It does lead to a couple more questions. I am going to look for a test kit. As I look online, I see Taylor is more available, but there are many models to choose from ranging in price from about $8 to about $60. Is there a recommdation for a model that has what I need but not extra tests that I don’t? Looks like I need FC, TC, PH, TA, CYA, correct? Do the kits tell you how much to add based on the results?

    Also, I use liquid chlorine shock from the pool store (sodium hypochlorite 12.5%) and supplement with 1 inch pellets in a chamber off my pump (some stores call it a frog dispenser or miser max Pac with trichloro-s-triazinetione). With this type of chemicals am I going to always run up against the cloudy water every so often due continually building CYA?

    The help is greatly appreciated!

  • Dontay

    Jon… your on the right lines. You can’t hope to sort problems till you have accurate info from the pool which will lead you to knowing what the cause of the problems are. If it’s CC giving you cloudy water it can easily be brought down by shocking the pool. Keep FC continually above 40% of CYA by testing FC and adding sodium hypo if FC appears to be dropping below 40%… keep doing that until the water comes clear ( it will!!! ) and then test CC… when it reads 0.5ppm or less you have solved the problem. The Taylor FAS DPD K-2006 test kit is probably the best one for you to test all the parameters you have mentioned. The only thing I would mention is that your PH and TA don’t appear to be problematic for you… which is quite normal in most outside pools, they should rarely need attention and your pool store test methods are usually accurate enough for those two,parameters. It’s FC and CC they fail on!!!… so you could probably get away with just buying the separate FC/TC and CYA test kits… but only LaMotte make those as separate kits. Your choice obviously! All FAS DPD type kits provide all you need including written instructions on how to carry out the various tests. There are also videos showing how to do the FAS DPD testing method on-line with both manufactures web sites providing a link to them. No they cannot tell you how much chemicals to add based on results… that’s due to every pool living in slightly different enviroments. Also bear in mind that your pool may even react differently even to a near neighbours pool… that’s one of the difficulties in providing advise!!! Every pool is different! With any of these kits you can test first thing in the morning and last thing in the evening and establish for yourself EXACTLY how YOUR pool is behaving during hot sunlight and also overnight… you can establish what YOUR normal chlorine demand is over any given 24 hour period AND any part of that period… and armed with that info you can work out how much YOUR chlorine demand is each day in order to stay healthy. Once you get to a healthy pool simply test the FC level, add say a pint of sodium hypo… and test again 30mins later… and you’ll know how many ppm’s it’s risen… from that you can work out how much you actually need to cover for YOUR 24 hourly chlorine demand and dose accordingly… from then on just stick to the routine CYA/FC ratios. I am familiar with the Frog! I strongly advise you turn it off! Frog’s and similar auto dosers used to be all the rage for residential pool owners until reports of problems started to appear. The minerals in the seasonal replacement inserts can lead to having high metal content levels in the pool which can cause staining on pool surfaces. Pool stores now do a roaring business selling ‘metal out’ chemicals!! You can stick a couple of slow dissolving tablets/pucks in them rather than using the pacs and they ARE handy as an alternative to dosing the pool to a higher level with liquid if you go away for a vacation and need to keep the chlorine levels up whilst your away… but that is all you should use the frog for. Just don’t bother purchasing the replacement canister every season! You should have no normal need to supplement sodium hypo with any other form of chlorine. YES, if you use the frog as a routine your CYA levels will keep rising because all forms of chlorine accept sodium hypo contain either CYA or calcium. Calcium also needs to be kept well under control and again the only way to reduce it is by way of dilution. Those comprehensive FAS DPD kits also test for calcium hardness (CH) but it’s normally well under the 350 ppm limit. Providing you have stayed stay away from shocking with calcium hypochlorite… which some manufactures actually like to call ‘shock’ (it’s no such thing!!)… CH will never go out of range… and so CH will hardly ever need testing for. Even worse calcium, unlike CYA, is also in normal water which makes it very difficult if you ever have to reduce the levels in the pool. YES with regular use of the frog with either tablets/pucks or the frog approved pacs… you run the risk of eventually getting into cloudy water most commonly algae related problems if you don’t also keep your FC levels to the correct percentage of your rising CYA levels. Your CYA level should be set in accordance with your normally expected summer ambient air temps… and KEPT there! CYA should never be less than 30ppm in outside pools and CYA at 30 to 35ppm is fine for most climates accept very hot ones that exceed 40C. Test FC daily and dose with sodium hypo to 16% of your CYA figure to allow for your 24 hourly chlorine loss. With a CYA levels in the 30-35ppm range try to aim to keep your minimum FC to beteen 3 and 4ppm and never less than 2.5ppm. Depending on your daily chlorine demand that may mean dosing to around 5ppm. Anywhere under 8ppm FC is safe for bathers PROVIDING you have CYA at a minimum of 30ppm. Test CYA every few weeks if you need to keep adding fresh water due to top ups or backwashing and keep a tub of CYA in case you need to add any. TA and PH can be tested once a week but TA isn’t a worry normally… if PH ain’t broke (and stays reasonably stable somewhere in the 74 to 7.8 range) then don’t bother fixing TA. The main criteria in an outside pool is to ensure your CC is 0.5ppm or less and your FC doesn’t drop below 7.5% of CYA and preferably stays closer to 16% of CYA. That keeps algae at bay and CC under control. CC can normally be kept well under control if minimum levels of FC are kept correct and also the pool is exposed to sunlight for the equivalent of two days a week… if you have a pool cover roll it back and let the pool ‘breathe’ every 2 or 3 days even if not used.

  • Brandi

    Someone please help. My pool readings are as follows:
    Total chlorine is 5.0
    Free chlorine 5.0
    Ph 7.8
    Total alkalinity 120
    Calcium hardness 250
    Stabilizer 20
    Phosphate 500.0
    Borate adjustment 0

    Step 1: I was told to put 1 qt of muriAtic acid in
    Step 2: stabilizer (but was told to wait on this until pool became unclouded)
    Step:3 use 23 oz proteam phosaway
    Step:4 after 2 days add 1gt chlorine remover (again told not to do this part)

    Here it is a week later. Pool is still cloudy
    Total chlorine is 0
    Free chlorine 0
    Ph: 7.3
    Ta: 125
    Ch: 250
    Stabalizer 20
    Phosphates: 475
    Borate 0

    I have been adding chlorine 3 bottles daily as recommended.
    I did vacuum pool as recommended. I did backwash like I was suppose to.
    I have an above ground 32×36 still cloudy.
    What am I doing wrong what do I need to do? I have been fighting this for right at 5 weeks each different things

  • Dontay

    Brandi… what type of test kit are you using? I am very suspicious that they may be incorrect and even if they ARE correct the advice you have received is incorrect. IF they ARE accurate there was not much wrong with your original readings except your stabiliser (cyanuric acid) is a little on the low side for an outside pool. 20 ppm IS ok but ideally It should be at a minimum of 30ppm in order to stop the sun from burning your FC away too quickly. Your FC and TC figures are exactly the same which is absolutely perfect… any difference between those readings is the level of Combined Chlorine (CC). In an outside pool the maximum CC should not be over 0.5ppm so yours are fine. There was also nothing wrong with your TA or PH. PH should be anywhere between 7.4 and 7.8 (inclusive!) Ideal TA is between 80 and 120ppm but it’s not a problem if goes outside that ideal providing the PH stays reasonably stable in its 7.4 to 7.8 range. TA… which is a measurement of various carbonates is harmless, it buffers’ the water and prevents wild swings in PH levels. PH over 7.8 CAN lead to cloudy water because chlorine ‘activity’ in the water slows down. Chlorine becomes less efficient. PH can wander around occasionally due to several factors… most common due to high bather load or heavy rain fall… disturbance of the water surface can cause it to rise… but more often than not, give it a bit of time and it settles back down again within a week. Phosphates are complelty harmless, it’s in the air we breath, in our soil and they are measured in parts per billion, (as opposed to parts per million) They are a plant nutrient and since algae is a plant… algae will feed on it… but if there are no algae spores in the pool then there absolutely no need for phosphate remover. The way to stop any problems is to stop algae getting in the pool in the fist place with correct FC chlorine control… and if algae DOES get in… then kill the algae by shock dosing… not by removing its dinner! Putting in Muratic acid (liquid acid) to lower the PH wasn’t necessary and I’m puzzled that your TA as risen. Acid normally lowers both PH and TA! Lowering your FC wasn’t necessary either. FC quite naturally only goes one way… and that’s downward on a daily basis as it gets consumed by the job it does in disinfecting the water, There was nothing wrong with FC at 5ppm… it was higher than your MINIMUM level you need for your 20ppm CYA figure. If CYA is 30ppm then your minimum FC level slhoud be 2.2ppm To ensure you don’t drop through that FC minimum it’s normal to dose the pool to between 4 and 5ppm to allow for daily chlorine losses (Chlorine Demand).

    There is STILL not TOO much wrong with your readings on the face of it… except your FC. THAT needs urgent attention right now! I am VERY suspicious of the accuracy of the test results and whoever has advised you. BUT… the way out of the most pressing problem now is to shockdose the pool with LIQUID chlorine (SODIUM HYPOCHLORITE) All pool stores sell it and you should purchase the highest strength they sell. IF your CYA is anywhere near a correct reading then you should pour in sufficient sodium hypo to raise FC to OVER 40% of your 20ppm CYA figure… that means raising your FC to over 10ppm. That is the chlorine oxidisation point (shockdose point) for a CYA reading of 20ppm.I would suggest you raise it initially to 15ppm. THEN you need to KEEP it least above your shock point! KEEP it there until your water comes crystal clear! You will need to test every 2 to 4 hours and add additional sodium hypo until the water becomes totally crystal clear!! IT WILL DO THAT!!! You may be lucky and it will only take a day for that to happen but be aware it it CAN sometimes take a few days!!! You will find that your FC will drop RAPIDLY at first but then demand will eventually slow down as the water clears… still ensure you keep it above shock point till it does! Stop making any more chlorine additions when it does. In order to follow this procedure you need a FAS DPD test kit. Only that kit will give you the accuracy of FC TC and CYA test readings you need. Taylor Industries and LaMotte are the most common makes and will cost around $80. FAS DPD KITS are Freely available on line. Until that arrives I suggest that you dunk around 12 gallons of sodium hypo in the pool to prevent algae getting established until your in a position to test properly.

  • JR

    I have a pool that is very cloudy. When I test the water it shows the pH, Alkalinity, and stabilizers at their proper levels. Unfortunately, the chlorine is non-existent regardless of how much chlorine I put in the pool. Any ideas on what this could be? I believe the sand in the filter is still in good shape but regardless that would have nothing to do with the chlorine levels.

  • Jon Rossiter

    while waiting for the Taylor FAS DPD kit to arrive, I decided to dilute by draining. I drained about 1/3 of the water out and refilled from the hose. Got the kit on Memorial Day and initially tested for CYA. It was 35ppm (after the drain and refill).

    During the drain I noticed a shadow in the center of the pool I could not see before due to the cloudiness. Got the net out and found it was a 3-4 foot pile of swamp smelling algae resting in the center of the pool. I manually vacuumed this to waste before refilling.

    After refilling and checking CYA, I checked the pH and Alkalinity. Water temp is about 80 F (been warm here lately). Got 7.6 for pH and 120 for TA. TA is on the high side of ok so I left it. I could see the bottom now although the water is still cloudy. Before I could only see 10-12 inches down.

    The FC CC were at 0 so I started by dumping in 2 gal of 10% sodium hypochlorite. Waited till the next morning and retested. Next day FC was 3.5, CC was 2. Still cloudy. Cleaned cartridge filter.

    Next day tested FC was 3, CC was 1. Realized that my % FC/CYA was only 8.5 so I added 3 gal of 10% sodium hypochlorite. Still cloudy, cleaned filter.

    Today we had rain so retested to confirm pH and TA were ok. 7.6 and 120 (same as before). FC at 7.0, CC at 0.5. FC/CYA is 20%. Still cloudy so I cleaned cartridge filter and added another gal of 10% sodium hypochlorite. I think this should take it up to about 40%, correct?

    While I am seeing improvement, it’s not clearing up as fast as I would have hoped. Any thoughts on how much longer it could take to get clear?

    Wife and kids are itching to get in. I’m itching to stop buying so much chemicals.

  • Dontay

    Hi Jon, firstly forget about testing TA, PH and CC levels for the moment. They sound fine and probably are…but at high levels of chlorine there can be a bleaching out effect of those test regents which can give inaccurate results so for now just concentrate on CYA and FC. The CYA ‘disappearing dot’ test is a water turbity test, it’s the most accurate way of measuring CYA but any turbity test has a plus or minus (+/-) margin of error of around 7%… even discounting any slight ‘operator’ errors. To allow for that it’s safer to assume its slightly HIGHER than you think it is and adjust the minimum levels of FC accordingly. Your CYA seems to be around 35ppm which is ideal and around that level suits most climates accept very hot ones that regularly exceed 100f. But to allow for that MoE it’s safer to say CYA is 40ppm. At 40ppm your absolute minimum FC shock level is approximately 16ppm. That is the point where chlorines oxidisation chemical reaction occurs that SLAMS the water and it starts to kill algae. Somewhere just below that level… algae WILL slowly die but it will take much longer. The other main point I would emphasises is the importance of continually KEEPING FC ABOVE that minimum level until the water hasn’t even a hint of cloudiness or haze left in it. In an algae contaminated pool the FC level needs to be taken well above the minimum because FC will drop very rapidly as it gets ‘used up’. You have had an algae bloom… that means there will be billions of algae spores in your water and so your FC levels will drop like a stone within 2 to 4 hours. To allow for that almost instantaneous drop… with a CYA level at 40ppm and a minimum FC shock point of 16ppm then you need in the early stages to raise your FC to 20ppm. Test again 2 to 4 hours later and you will find its dropped towards your minimum 16ppm. Make a note of what that level is!!! Raise it back up to 18-20ppm if it’s dropped below that! It is VITAL that you don’t let your FC fall below that 16ppm level. Continually test every 2-4 hours and add more chlorine if it seems to be getting TOO close to your minimum for comfort!! Repeat this procedure until you notice that your chlorine demand is slowing down and FC is taking longer to get to 16ppm and you don’t need to add so much chlorine to stay above level. That means the algae is on its last legs! Throughout this procedure brush ALL surface twice a day and keep the pump running 24/7. Only backwash/clean the filter if or when your pressure rises above 25% above normal clean water pressure… there is no benefit in continually backwashing. Due to the start you have made I doubt this will now take more than a couple of days… you should start noticing the difference after 24hours. Start first thing in the morning and monitor it every couple of hours throughout the day, testing and making chlorine additions as required and by late evening you will probably be able to dose to 20ppm and leave it to drop overnight. It MAY drop past 16ppm by the next morning (but I doubt it) but just take it back up to 20ppm if you need to… and KEEP going! ONCE you have totaly crystal water you then need to do an OCULT. It’s very simple! It’s an ‘Overnight Chlorine Loss Test’ There are 3 parts to it. FIRSTLY you need to see crystal clear water with your FC STILL above your 16ppm minimum… once that is apparent KEEP FC above minimum just for that day until dusk. SECOND part of the test: NO sun on the water! Test FC and note the level… obviously it’ll be somewhere above 16ppm! Turn off the pump…. don’t add anymore chlorine!!!!!! Test FC again the next morning BEFORE any sun is directly on any part of the pool. You may have to reset your alarm clock! IF FC has only dropped by 1ppm you have passed the second part of the OCULT. THIRD part of the test: test for CC. IF CC is 0.5pp or less you have passed the third part of the OCULT. Congratulations!!! You have now completed the shockdose procedure and you can allow your FC to drop to normal levels over the next few days. It’s safe to enter the water… even for the kids once it’s dropped to 8ppm. It won’t take long to get there! Also once below that level check your PH and TA. If PH is in the 7.4 – 7.8 range don’t worry about TA. TA is harmless but acts to buffer the water against BIG swings in PH readings. If PH stays stable don’t worry about fixing TA even if it some way out the 80 -120ppm range. Many pools do just fine. If TA ever gets above 130ppm it’s best to get it back down because if it gets TOO high it can make it difficult to lower PH if you ever need to… simply because the acid we use… gets ‘taken up’ by the alkalinity before it act on PH. PH at 7.8 or under is fine. The are 100 times difference between the individual points on the PH scale. 7.9 is a one hundred times more alkaline than 7.8 so no need to spring into action with chemicals just because you think your getting close to the limit! The way to higher PH if it becomes more acidic and drops below 7.4 is to get the kids splashing around in there with a load of friends… no need for chemicals! Before starting shockdose you should also remove anything that algae can hide behind… ladder fixings are a notorious hiding point! any underwater light covers should also be removed and left out… the niche should also be cleaned/wiped out and left open to circulating water. Anything removed should only be replaced once OCULT has been passed. If any part of OCULT is NOT passed…. stay above shock level unti it is. If we assume your CYA is 40ppm then your normal MINIMUM FC is 3ppm. You should NEVER allow FC to drop below that figure!!! Your MAXIMUM FC level is 5ppm. That means in an average healthy pool you should not need to daily dose to more than 5ppm to ensure FC does not drop below 3ppm over any 24 hour period. With CYA anywhere above 30ppm…. those FC levels are safe and fine… even for young babies. Best of luck Jon… come back if you are still unsure.

  • Dontay

    JR… it would be good if you can say what kit you use to test with and also what you think your PH, TA, FC, TC, CYA levels actually are in ppm figures. Also what type of chlorine do you use, i.e. stabilised tablets or powder or calcium based powder (hypochlorite) or liquid hypochlorite (bleach) Knowing your approx size of pool and/or water volumes would also be helpful in helping you.

  • JR

    Approx. pool gallons is 14,000
    I use an AquaChek test strip with the readings in ppm
    Free Chl. 0
    pH 7.8
    Total Alk 180
    Stabilizer 75
    The exact chlorine being used is tablets but I’m not sure on brand or chemical make-up. This is a customer of mine’s pool and they use their own chlorine. I did put 10 pounds of shock in 4 days ago. Shock is 73% calcium hypochlorite.
    All readings are from this morning.

  • Dontay

    JR, it’s not really a surprise your customer has ended up with cloudy water. I expect the aqua check test strips are the ones you stick in a digital analyser and get a read out in ppm’s. Sorry but test strips of any description are a waste of money. Proper pool Testing chemicals are known as regants and they have a ‘use by date’ because they degrade over a period time… usually a couple of years. They have to be kept in a cool dark place away from sun light and bright shop lights…I.e. back of a cupboard! The row of pads on test strips are impregnated with test regant, they are made in their millions, shipped all over the planet and spend most of their lives in either the makers warehouse or haging from shop shelves… they generally are not stamped with a use by date either! Even with a fancy looking analyser they are basically just toys. In the TA parameter even AquaCheck themselves admit the analyser is only accurate to plus or minus 30ppm!!! All this means that the figures you have provided are most likely meaningless. However on face value TA is miles too high and should be somewhere in the 80 -120ppm range. PH is ok… anywhere between 7.4 and 7.8 inclusive is fine. The CYA (stabiliser) at 75ppm is miles too high. Unless normal air temps regularly exceed 100f… CYA should be no more than 40ppm. High levels of CYA require increasingly higher levels of chlorine. CYA at indeterminate levels above 60ppm can bring chlorine ‘activity’ in the pool to a complete stop!!! CYA is a must have in an outside pool because restricts UV light from burning away chlorine too quickly. In an outside pool with zero CYA… the hot sun will burn away 3ppm of FC in under a couple of hours. So you need some… but not too much! Minimum FC with CYA at 30ppm should be 2.2ppm. Minimum level of FC with CYA at 75ppm is 5.5ppm. Chlorines shock point with CYA at 30ppm is 12ppm. The shock point with CYA at 75ppm… is 30ppm!!!! Chlorine tablets are ‘stabilised’ regardless of who makes them. So every time you dissolve a tablet you increase the CYA level!! There is only one way to lower CYA levels…. water dilution! There is no chemical that can do it for them. Rule of thumb is: Drain away 50% of water and top back up with fresh then you also reduce the CYA level by 50%. CYA is a man made product… it’s not present in normal water. They also use calcium hypochlorite to shock the water. They need to stop doing that. Calcium is another ‘ingredient’ that cannot be reduced by chemicals… only by water dilution. It’s more difficult to do than CYA because normal ‘fill’ water has levels of calcium already in it!! The max calcium level (calcium hardness… (CH) ) is 350ppm. Over that figure and you can introduce staining on the pool surfaces, scaling in the pipes…. AND cloudy water!!! So there are two possible causes for your customers problems…. calcium may be over 350 ppm… although that’s rare … they have been using calcium hypochlorite so has to be taken into consideration. The most likely cause is the chlorine is virtually ineffective due to the high CYA. In order to resolve anything they need in the first instance to be able obtain accurate info from the water. They need to purchase a ‘proper’ pool test kit to do that. There is only one that gives accurate info when shock-dosing a pool and chlorine is at high levels.. It called an FAS DPD test kit. Taylor Technologies and LaMotte are the most common makes. Google FAS DPD test kit and you’ll find them… probably around $80 for the basic Taylor K 2006 kit. That kit gives all they need to test all normal pool water parameters. I suggest they order that and whilst waiting for it to arrive they start draining away at least 50% of the water volume and replace it with fresh water. Avoid doing it all in one go… it should be done in stages… no more than a couple of feet of water before topping up before proceeding to empty more out. CHLORINE!!! They need to swap over to liquid chlorine called SODIUM hypochlorite. All pool stores sell it. Strengths vary but get what they sell locally. ALL other types of chlorine add either CYA or calcium to the water. Liquid chlorine adds a small amount of harmless salt. It can be used as a normal daily chlorine additive as well as a shock. With around 14,000 gals of water a couple of pints of sodium hypo will probably increase FC by around 2ppm but that can be ascertained once they can test properly and regularly. Once they are in a position to do that, and CYA is down to 30ppm…. forget about PH, TA and CC. Just raise FC to 16ppm… KEEP it there by testing every 2 – 4 hours… adding sodium hypo as required to KEEP FC above 16ppm until the water becomes crystal clear… it may take a couple of days… and then resolve any outstanding PH or TA issues when thing return to normal.

  • JR

    Thanks for the wealth of information. I should also add that it has rained ALOT this spring and has caused us many problems with pools. I have started researching new testing methods. Do you recommend one over another? I’d like to have a digital one in order to keep it in my truck while I am working instead of having to take it back to our store to get the reagent out of the “back of the cupboard”.

  • Dontay

    JR, pool stores use various types of digital read out machines. They are used in conjunction with tablet reagents. Take the same sample of pool water to 3 different pool stores and you will most likely end up with 3 different results across the whole range of pool water test parameters. There are various reasons for that. The machines they use cost many hundreds of dollars and they ‘read’ the light spectrum and are pre-set to compare the density of water once the applicable regent has been added. They are NOT accurate because they are unable to detect vary slight differences in density… (depth of colour)… those slight difference can have a large degree of difference in the actual ppm read out results. They also need regular recalibration, ideally at least once a month… with most stores you will be lucky if they arrange for recalibration once a season! Also the tablet regents they use have probably been on nice warm, brightly lit shop shelves for a very long time. The main problem with tablet test kits though is they can be very inaccurate even in a newly calibrated analyser and even if the tablets are in date and stored in ideal conditions… when high levels of chlorine are present in the water sample. They suffer from a ‘bleaching out’ effect… chlorine IS a bleach and that is exactly what chlorine does to tablet reagents… it bleaches the colour out of them. There is ONLY one type of kit which does not have that bleach out problem… and that’s the FAS DPD droplet count test kits that I mentioned. Also the CYA test component in these kits is known as a ‘disappearing dot’ test. It’s a water turbity test and is the most accurate CYA test on the market. Even so… it’s only accurate to around plus or minus 7ppm… introduce slight operator errors and the results could be out by much more. All other CYA test kits can be ‘out’ by well over 15ppm even without any operator errors. Since CYA levels in any outside pool should not be below 30ppm to protect chlorine from UV light… and since FC ABSOLUTE minimum level should NEVER be below 7.5% of whatever the CYA level actually is… it’s vital to get the most accurate CYA results that are possible. It’s normal to do 3 test withe same sample and use the average of the 3. Then STILL allowing for that CYA margin of error… make the assumption that the result is on the high side and stick another 1ppm on the minimum FC level… just to be on the safe side! ABSOLUTE Minimum FC levels are 7.5% of whatever the CYA level is. PLUS then allow another 1ppm for the FC. Maximum FC needed on a daily basis, in a normal healthy pool… to ensure the minimum FC isn’t crossed is 16% of CYA. Get all that right and kept right there should never be any problems with algae.

    Shock-dose ABSOLUTE minimum is 40% of whatever the CYA level is… and in the early stages of shocking a pool FC needs to be taken to at least another 5-6ppm above that 40% level AND It needs to be KEPT above that minimum level until the water becomes crystal clear. The FAS DPD type kits come in a sturdy plastic case and the levels of individual reagents are usually sufficient for one season of normal use in a residential pool. If you intended to do lots of testing then you will probably use up the test reagents before any storage problems can have any effect on degrading them. You in fact may need one of the commercial size kits that both Taylor and LaMotte make for pool maintaince professionals. Even fire fighting one severely contaminated pool can easily use up the reagents in a normal kit. These kits also have two levels of accuracy… for normal use the first accuracy level of plus or minus 0.5ppm is fine. In exceptional circumstances you can, if required, also test to an accuracy level of 0.2ppm. That level uses more regents in a larger sample of water. If you go the digital route you will almost certainly run into continual hard to resolve problems due to a lack of accurate information from the water. Many people rely on pool stores to test their water samples for them, quite naturally believing they must be the experts… and know what they are doing… they couldn’t be more wrong! Pool store exist to sell chemicals and the more they can sell the more they are likely to stay in business! Accurate info and results are vital and only the FAS DPD type kits will give you that.

  • Scott

    I have cloudy water but my chemicals are right on according to two pool stores. I think the dead algae is recirculating in the pool and is too small to be caught by the filters. I am to the point of flocking, but I have cartridge filters (inground pool) and no vacuum to waste port/valve. How do I vacuum out the flock then? Some possible ideas from reading about this:
    1. Is there some sort of manual vacuum that hooks to the hose? How does this work?
    2. Can I open the drain plug in my cartridge filter housing and vacuum to waste that way somehow?
    3. After I flock will that mess up all my chemical levels again?
    Thank you for any help you may have to offer!

  • Dontay

    Hi Scott, it sounds like you are another victim of the pool stores notorious ineptitude! Dead algae isn’t too small to be filtered with any reasonably efficient filter… and if it IS dead algae you don’t remove it by using flock. Can you give some more specific info? Why do you suspect it’s dead algae? How did you kill the algae in the first place? What type of chlorine do you use, (stabilised or hypochlorite) as routine and for shockdosing? You say the pool stores report the chemicals are “right on” what does that mean? For instance… when tested was your FC at its minimum level, target dose level or shockdose level? What were the ppm’s for TA, CYA, CH, FC and TC, also what level is PH. There is only one way to sucssefully kill algae and that is to raise FC to above your shock point level in continually circulating water and keep it above that shock point until the water becomes clear. Flock won’t do anything. Your minimum shock point for FC is 40% of whatever your CYA level actually is, so if you DO have dead algae giving cloudy water after shocking… your FC should still be above that 40% level.

  • Scott

    Thank you so much for your help. I am so tired of being “pool stored!”

    Ok, we took the cover off the pool 3 weeks ago. The water was clear but was green on the bottom. The pool store told me to put in 9 lbs of Super Shockwave. A few days later they said there was no chlorine and told me to put in another 5 lbs of Super Shockwave and some algaecide. A few days after they said the readings said still no chlorine and told me to put in another 10 lbs of Super Shockwave, which I did not do. I went to another pool store at that point. The new store told me first I needed 4 lbs CYA, then 4lbs shock with stabilizer, and another 1/2 gallon of algaecide 40, which I did. It is a 25,000 gallon pool with 4 cartridge filters. I then took the cartridges out and rinsed them out and put them back. I then ran the Kreepy Krauly for about 12 hours to clean the bottom of the pool. The water was cloudy for several days after so the 2nd pool store said to use 4oz of clarifier, which I did around the edge of the pool. 2 days later it was a little better, so I added 4 more oz of clarifier. It is still cloudy, and that’s where we currently stand. The water is not green anymore but I can barely see the bottom in the shallow end. I run the pump 24 hours a day. It is a salt system.

    Results of today’s water test:
    Free Chlorine: 0.42 ppm
    Total Chlorine: 0.67 ppm
    Combined Chlorine: 0.25 ppm
    PH: 7.5
    Hardness: 119 ppm
    Alkalinity: 111 ppm
    CYA: 43
    Copper: 0
    Iron: 0.1 ppm
    Salt: 2700

  • Scott

    This is a before shot of the pool to see how far its come so far.

  • Dontay

    Scott… yep, you got algae and your sad story has been told and retold countless times. You got it right… you’ve been pool stored! Looking at your picture you now need to get back to basics and stop relying on pool store water sample tests, which are almost always inaccurate and so is their advice. They unfortunately are not experts in pool water care but they are certainly experts in talking you into buying chemicals! More often than not chemicals you don’t need and/or the wrong type of chemicals. Only one person you can rely on to test your pool accurately… yourself… and for that you need the correct test kit to cure the problem you have. You also need to be on site and available every 2-4 hours in order to continually test and treat the water. Clearing algae is not rocket science, you don’t need any special skills but you do NEED to obtain good quality and accurate info from your water. There is only one way to do that! Purchase a FAS DPD testing kit. Most Poole stores don’t sell them but they are readily available for purchase online. Simply Google FAS DPD test kits and you’ll find them. Simple and easy to use with a crystal clear ‘end point’ so no colour comparison or inaccurate digital analysers that the pool stores use.. they are the most accurate kits you can buy across the whole range of test parameters and absolutely vital at the high chlorine levels you are going to have to go to. Taylor and LaMotte are the most well known ones, the Taylor K 2006 kit cost around $80 (you may well find it much cheaper) and in medium and long term save you hundreds of $$$ in chemicals. The way to clear water is to raise FC to ABOVE your specific shock point. YOUR specific shock point is around 40% of YOUR cyanuric acid (CYA) level. CYA tests are a water turbity test, turbity tests have a plus or minus margin of error. Pool stores do not generally use the CYA ‘Disappearing Dot’ test and can be ‘out’ by as much as 20ppm. The FAS DPD kits contain the CYA disappearing dot test. This is the most accurate CYA test on the market but even so has a margin of error of around 7ppm. Chlorines shock point which is the point where the chlorine level reaches its oxidisation point needed to kill algae is around 40% of CYA. Since chlorine is ‘used up’ VERY rapidly in algae contaminated water it’s very important to go well above the shock point AND keep it there. Your CYA figure (if accurate) is 43ppm… so your FC shock point will be a little over 16ppm. I suggest you go to at least 20ppm to start with. You DO need one of those test kits so you know for sure that is where your at. Once you have dosed to 20ppm you need to retest every 2-4 hours and add more chlorine to STAY above the shock point. IT CAN… and looking at the colour of your water… probably WILL take several days. Eventually your chlorine ‘demand’ will slow down… it will take longer to drop towards your shock point and it will take increasing less amounts of chlorine to keep it just above your shock point. You will notice your water turn milky white and eventually the bottom will come into view. All those signs are of algae dying. It will slowly become crystal clear. On the day it becomes TOTALY clear, without even the hint of haze left in it and it’s visually sharp and sparkly as a diamond you need to still keep above shock point until dusk of that day. You then need to do an Overnight Chlorine Loss Test. (OCULT). Turn the pump off. NO more chlorine and test the FC level… it should still be at shock level of just above. Note the result! The next morning BEFORE any sunshine is on the water… retest the FC. If the overnight chlorine demand has been 1ppm or less you can then do the last part of OCLT. Test the CC. if CC is 0.5ppm you have sucsefully completed killing all algae spores in your water and you can now let chlorine levels drop away over the next few days. If you fail on either one of those test results you need to keep going, keeping FC above shock level and do another loss test the next evening. before starting this shockdose procedure you need to remove andthing algae can hide behind… ladder fixings and underwater light covers are typical items that need to be removed and cleaned with a chlorine solution and left out until OCLT is passed. Any niches or recesses should be thoroughly cleaned out and left exposed to circulating water. Algae has spent millions of years in defending itself in hostile enviroments and is extremely tenacious. It doesn’t give up easily and it can recover to multiply again if any spores are left alive. Chlorine comes in 3 basic ‘types’ the most common used one is stabilised chlorine. Stabilised mean it contains CYA. CYA cannot be lowered other than by water dilution. Since it’s not present in normal fill water if you drain away 50% of a given volume of water and top up with fresh, you also lower CYA by 50%. The next ‘type of chlorine is Calcium Hypochlorite. That’s what the pool store have been selling you. There is no such thing as a product called shock regardless of what the makers call it. Shock or shocking the water is a procedure… not a product. Calcium levels can also only be lowered by water dilution… it’s more problematical tha lowering CYA because it IS in normal fill water. Levels of calcium can very across the country. Calcium Hardness (CH) should not exceed 350ppm. To do so can introduce stains on the pool surfaces, scaling in the pips and cloudy water. Your CH figures are a long way from the max allowed so your probably OK on that… but it’s not a good idea to use calcium based chlorine to shock the pool… you can send the values soaring when used in shock quantities. The remaining type of chlorine is liquid bleach. Liquid chlorine known as Sodium Hypochlorite. This is what you should be using. It doesn’t add unwanted CYA and it doesn’t add unwanted calcium. Simply a small amount of salt. It comes in various strengths and all pool stores sell it. It’s probably the cheapest form of chlorine you can buy! A 25,000 gall pool will probably need around 4-5 pints to raise FC by around 2ppm but that is easily ascertained once you can test the water properly. Test FC, pour 4pints of sodium hypo split between the returns and test FC again 30 minutes later and you’ll roughly how much you need to get to ABOVE shock point.
    NO more algeacide! High chlorine levels destroy the chemicals that make up algeacides. You just as well throw your $$ in the water! Throuout this shock procedure keep the water circulating 24/7 and you should MANUALY brush all pool surfaces twice a day. Only backwash if the pressure gauge shows 25% above your normal clean water pressure. Their is no advantage to be gained by continual backwashing. Vacuumed should also be done manually and carefully but only once the bottom comes into view… there is not much benifit in vacuuming until then.

    The CYA level that suits the majority of climates is so where between 30-40ppm. 35ppm reading is ideal because due to the turbity test margine of error it’s safer to ASSUME it’s 40ppm and work the FC from that figure. In chlorinated pools minimum FC is 7.5% of whatever the CYA is… so at 40ppm the FC minimum is 4ppm. Daily FC target dose will be around 5-6ppm depending on if the pool is covered over when not used.

    When you stick chlorine in the water a percentage is instantly converted to Hypochlorous Acid (HOCL).Thats the disinfecting agent in chlorine that we call Free Chlorine (FC) The percentage that’s created is dependant on the PH level. HOCL is a highly unstable molecule which dissipates rapidly in the presence of sunlight. Proper stabilisation of HOCL with CYA seriously slows the rate of dissipation by the sun without appreciably sacrificing oxidisation & disinfection activity. HOCL reacts with substances other than water to produce ammonia which in turn produces chloromines, this occurs in several stages with HOCL (FC) consumed at each stage. With FC kept at correct levels and the water exposed to sunlight for the equivalent of 2 days a week CC rarely becomes a problem in an outside pool… and UV sunlight is a very effective and free way to keep them under control! Anywhere between zero and 0.5 ppm is fine. ONLY when CC has got above 0.5 ppm do you have to shock to get them down. THAT it easily and quickly done… usually within a day or so.

    Algae is a different matter and unfortunately the most common and persistent problem and I’m afraid salt sanitised outside pools are not so effective at keeping algae at bay. Fine for indoor pools but most folk find chlorine more effective in the battle against algae.

    HOCL (FC) also easily dissociates into an ionised hypochlorite state called Hypochlorite Ion (OCI). The balance between HOCL and OCI is effected by PH levels. The higher the PH the less HOCL is present… and so FC is less effective. At a 7.2 PH roughly 66% is of chlorine is effective FC (HOCL) At PH 7.8… around 33% is effective FC ( but that’s fine!) if above 7.8 then immediatly get it down!

    Now then…. CYA shields a percentage of HOCL from the sun by moderating it’s strength and also by ‘binding’ a percentage of it and holding it in reserve… that ‘held back’ proportion is released in direct proportion to the the amount of ‘unbound’ FC as it is consumed. IF you chlorinate to 3ppm in an outside un-stabilised pool… then in noonday sun that 3 ppm of FC a will be gone in an hour and a half… the vast majority of it taken out by the sun! So it’s vital to have CYA in an outside pool but FC is ALL about percentages!

    The higher the CYA level then the higher your FC level has to be in order to allow for that ‘bound up’ FC percentage. The hotter the sun the more intense the UV and the more rapidly the ‘unbound’ FC gets eaten up… so the more rapidly CYA ‘bound up’ FC also gets released and eaten up! SO… the hotter your normal ambient climate the higher you should have CYA to protect against loss and therefore the higher your FC level should be! It’s ALL about percentages!
    It’s not important but just for info… the FAS DPD test kit shows the total amount of FC… unbound and bound. Best of luck Scott… Get one of those kits, use sodium hypo and you’ll be well on way to clear water. Anything your not sure about please don’t hesitate to get back.

  • Scott

    Thank you. Are you sure you are looking at the current picture of the pool? I posted both before and current photos.

  • Dontay

    Scott, probably the before pic. It’s the only post from you that seems to be visible. From what you say the water is looking much better currently. Which given the amount of chlorine you have stuck in so far is obviously to the good and therefore it may not take much longer to see it off completely. What I have stated still needs to be followed through. What you have done so far has started to kill the algae. Algea WILL die slightly below shock level but it will take much longer from where you were with a green pool and a high risk that you’ll give up before doing the OCLT test. If you do that… algae will start to multiply again and you’ll be back where you were. Pool stores actually rely on you to NOT finish the job. The chemistry industry, almost without exception advocate shocking the water on a regular basis. Folk fail to shock the pool to proper completion DO have to do that because they never learnt how to completely irradiate the algae spores. What they are doing is continually keeping algea spore under some semblance of control. The chemical industry would prefer you to keep doing that. You’ll keep going back once a month for large quantities of chlorine. It’s just a way of persuading you to keep buying chemicals. A properly run and healthy pool should NEVER need shocking. Shockdosing does is not a ‘preventative’ exercise, it doesn’t prevent anything… It’s a cure for when for some reason your daily disinfection routine drops below the minimum level required to stop algea spores settling in the water. Once they have done that, routine dosing is overtaken, it’s simply not strong enough to kill algea, hence you then need to raise FC to its oxidisation level to do that. The chlorine oxidisation levels with CYA present are; CYA at 20ppm = FC 10ppm. 30ppm = 12ppm. 40ppm = 16ppm. 50ppm = 20ppm. 60ppm = 24 ppm. Folk who have CYA levels above 60 ppm accept that they have to live with much higher levels of FC to stay correct with routine CYA/FC ratios and find its much cheaper to dilute the water and lower CYA levels if they ever have to start shock procedure… due to enormouse volume of chlorine required to reach and stay above chlorines oxidisation levels.

  • Scott

    So we need to add shock? With a salt system can we add straight chlorine? How much should we add to get it to 20ppm in a 25000 gallon pool?

  • Dontay

    Scott, yes you can add liquid chlorine. Despite all the fancy names the makers give it…. chlorine is chlorine is chlorine! Liquid chlorine is no different from any other type of chlorine… it just doesn’t also increase the levels of other things that you may not want…. i.e CYA or calcium. A 25,000 gall pool will probably need around 4-5 pints to raise FC by around 2ppm but that is more easily ascertained once you can test the water properly. All pools respond slightly differently but the most assured way is to test FC so you know where you are starting from… then slowly pour 4 pints of sodium hypo, split between the returns. Then re test FC again 30 minutes later, liquid chlorine will be fully mixed into the water… and you’ll then get an idea of how much you need to get to 20ppm. If the water is already partially cleared of algea you may then only need around four pints every few hours in order to keep it above 16ppm.

  • Scott

    Thank you so much for your help. So by Sodium hypo you mean liquid bleach? Like Clorox? Just to confirm – we should add 5 gallons of Clorox bleach to our pool to get the chlorine up to 20 ppm? Current pool pic attached.

  • Dontay

    Scott… sorry but for some reason the site is still not showing me your current situation. No worries, your water is probably an opaque white colour which is quite normal. Think of it as unconscious algea… dying but not yet dead!!! Yes Sodium Hypoclorite is simply liquid bleach. The other forms are simply a powdered version of bleach or also available as a slow dissolving tablet/puck. But it’s all bleach. Pool bleach has a stronger hypochlorite solution than normal household bleach. Household bleach is generally around 3-5% strength. Pool bleach is commonly either around 7-8% or even 12% depending on who your pool store suppliers are. Usually the higher the strength the more expensive it is. It makes no difference to the parts per million figure… that’s the volume… at the end of the day there will be little difference between using 8% or 12% solutions. Sodium hypo has a small amount of salt added in the manufacturing process but other than the hypochlorite solution the rest of it is just plain water. You CAN use household uncented bleach if you want to, it may even seem cheaper… but you may need it for longer due to its comparatively weak strength so probably not much to be gained. Yes, around 5 gallons seems about correct to get to 20ppm in 25,000 gal volume of water but the only sure accurate way is to test it with a 4-5 pint sample dose as I suggested. How long you have to keep it above 16ppm then depends on the level of contamination. Even a once deep green pool that is now an opaque white will still have some way to go, there are still billions of spores to be got rid of so have no doubt… you WILL use that much and more before your through! Obviously getting to oxidisation level may seem to use the majority of it but depending on the contamination level it can sometimes take that much again and more to get to clear water. Deep green pools can turn opaque white within a day of reaching oxidisation level…. but getting from white to crystal clear can take several days of adding chlorine to stay above oxidisation level.

  • Scott

    Thanks so much for your help. One last question. With the CYA at 43, how long will it take for the pool with 20 ppm chlorine to actually be swimable?

  • Dontay

    Scott, it’s not possible to say how long it will take, also you need to PROVE that your CYA is around 43ppm before you start. At the moment you are relying on the pool store test… pool store testis are notoriously way off beam. You DO need to buy a FAS DPD test kit and prove things. Accurate info is not only at the very heart of treating a contaminated pool, ONLY an FAS DPD kit can accurately test FC at shock level so you know for SURE that you are above the oxidisation point. Once you know for sure where you are with the CYA, then you can go to the correct chlorine oxidisation point and keep it above that point until the water comes totaly clear and your in a position to do the OCLT. Even when the water IS clear if you fail the OCLT then you have to keep going… failure means there is still some on going disinfection activity still in progress even though the water may appear to crystal. If you stop before completing the OCLT the remaking algae spore will rapidly rapidly start to multiply again…. It may only take a couple of days once you get started… it may take longer… from where you are now thats hopefully all it wil take but depends on how many billions of algea spores are still in the water. Safe swimming levels with CYA at around 43ppm is FC at 8ppm. After completing the OCLT it will probably only take a day or two together back down to that level.

  • Dontay

    … additionally… and going back to your original post… you stated that the pool stores recommended you to increase your CYA levels. That was absolutely the wrong advice for anyone with an algea contaminated pool. You have (according to THEIR CYA test result) and due to the amount of CYA you have used…. substantially increased CYA to 43ppm. You will see from the CYA/FC oxidisation points I gave you (which are taken from the professional CYA/FC correlation chart) … that CYA at 20ppm only requires FC to be raised to 10ppm to reach oxidisation point. If the pool store CYA test figure is to be believed you now have to go to at least 16ppm. The message is… the lower the CYA the less chlorine is required to get to oxidisation point. You never will know until you can test properly if your true CYA level is less or more than 43ppm. It will depend on what your CYA level was before you increased it but If your lucky then it maybe considerably less than 43ppm. If your unlucky it maybe considerably more. If it proves to be considerably more than 50ppm then it is usually more economical to reduce the level by dilution before raising FC. If you need to go down that route I suggest you lower it right down to 20ppm… you will not then require so much chlorine. CYA can always be re-adjusted to suit your ambient climate when things return to normal if necassary. Minimum CYA in any pool is 30ppm for normal chlorine protection from UV light… also any adjustments that may need to happen in any of other parameters are also best left until then.

  • Dianne Thomes

    I have a saltwater above ground pool. I use a saltwater filter and a sand filter. It was left up over the winter and leaves left it murky. It was to the point of clean but very cloudy. The ph was high so I added ph down, which lowered the ph a little but still cloudy. I also used a crystal clear agent without luck. Last night I got frustrated a put in 16 oz of the non chlorine shock. This morning it’s all brown! I had, and will continue to backwash daily. What next?

  • Dontay

    Hi Dianne… in order to come to an accurate diagnosis and a plan of action to clear up any water problems we need first of all to get good quality and accurate info from good quality test readings for Calcium Hardness (CH) Total Akilinity (TA) Cyanuric Acid (CYA) Free Chlorine (FC) Total Chlorine (TC) and also PH. Although some of these results maybe zero we still need to know that. A saltwater pool is also a chlorine pool if you need to clear up contaminated water.

    I’m afraid generalisations like PH was a bit high and is now a bit lower are not much help. We need all the water test parameters mention above in standard ppm figures. Also having a rough idea of your volume of water and the type of pool i.e. concrete and tiled, plastic types or vinyl lined can be helpful in the diagnosis. Unfortunately you cannot rely on pool stores to accurately test water samples or give you correct advice. Pool stores are notorious for only being experts at giving you incorrect advise based on inaccurate sample readings and selling you lots of chemicals! There are countless stories of pool owners being ‘Pool Stored’!!!!

    There are numerous test kits on the market but there is only one TYPE of test kit on the market for residential pool owners that can give you the high quality info you need in order to come to an accurate diagnosis and formulate a plan to clear up your water. Without that info you will be blundering around in the dark and like so many others… will probably still end up with cloudy water after spending a fortune on chemicals. These kits are known as FAS DPD test kits.

    Taylor Tachnologies and LaMotte are probably the most commonly used and well known makers of these kits, but there are also others. Most pool stores don’t sell them but they are available to buy online. Simply Google FAS DPD test kits and you will find them. Approx cost of a Taylor K 2006 kit is around $80 but you may find it for considerably less. These kits contain all you need for normal residential pool water care, very easy to use with a simple droplet count test with a totaly clear water end point… so no need for inaccurate digital analysers or trying to differentiate between different colour shades that you have to do with tablet tests. If you normally use test strips you should bin them. No accurate diagnosis is can be made from any sort of test stirip and no chemical procedures or changes should be undertaken based on their results. FAS DPD kits have complete home user instructions on how to test the various water parameters and there are also online video links. In the long and medium term a FAS DPD kit will save you from throwing hundreds of $$$ of chemical into your water trying to resolve problems. All algea related problems, which MIGHT be at the source of your trouble, also require you to test the water every 2-4 hours, sometimes for a quite a few days until the water clears… so you obviously need the kit permanently on site!

    Most of the highly trained and qualified in pool care maintenance professionals use them and the manufacturers also make larger commercial sized FAS DPD kits for them. Unfortunately the maintaince people that some pool stores employ are not usually in this bracket.

  • Dianne Thomes

    Thanks Dontay. After reading over numerous posts, I knew expected your response. The pool store I used prior to last year usually was right on. Their high tech test equipment impressed m to say the least. I always struggled before I started going there. But that was expensive, last year I bought the titanium plate salt filter and a large sand filter and had perfect water and had a very cheap trouble free crystal clear pool all summer. I’m sure with all the advise that you’ve given, I should find results. One things that I never seem to read anywhere on pool blogs is: why does some water turn almost instantly brown when shock or ant type chlorine is added? The past 5 years mines done this. For 20 years prior, same home never ever had this. Does it have to be a change in the city supplied water.? By the way my current pool is a cheap 18″ index pole type, with vinyl liner. But s pool , is a pool and I love it! Thanks again!

  • Dontay

    Dianne… of course you LOVE your pool, glad to hear it! I don’t know why your water goes brown but it shouldn’t be anything to do with the water supply. I would say it’s a chemical reaction of some kind to whatever is giving you cloudy water in the first place… I can only suspect it’s a reaction from Chloromines to the non chlorine shock you have used.
    Non chlorine shock works differently than chlorine. It will not break down chloramines but rather helps prevent them from forming if a residual is in the water at all times. This usually means means weekly addition of the non chlorine shock.
    It will also test as CC unless a special reagent is used to remove the interference during testing. It generally cost you more money than chlorine. For an outdoor pool it’s an unnecessary expense. For an indoor pool it does have certain benefits in terms of indoor air quality and redection of CC since an indoor pool gets no UV light from the sun and the UV light is part of what breaks down CC when you shock with chlorine. Normal chlorine that is :)

    In view of what you say I’m therefore suspecting the first issue…cloudy water… could be due to chloramines… they WILL rise if PH climbs above 7.8 because the percentage of FC’s effectiveness drops and so normal disinfectant activity in the water is weakened and slows down. If PH is quickly lowered back to 7.8 before the Chloromines cause any problems and the water left is also left exposed to sunlight then CC levels will generally fall back… if they don’t then the only answer is to shock the pool. That needs to be done with liquid chlorine. Chloramines are the compounds we refer to as combined chlorine (CC). These compounds are basicly a combination of used up chlorine and the bacteria that the chlorine has killed. High Chloromines are actually much more dangerous to human health than high chlorine levels… and in an indoor pool have to kept pro-actively under control. In an outdoor pool they don’t normally cause any problems because UV by way of sunlight is very effective in assisting routine chlorine levels to kept them under 0.5ppm. In order for the Suns magic to work in that way… a pool needs to be exposed to it with any cover rolled back even if not intending to use the pool… for around the equivalent of two days a week. If the CC level has risen and is now higher than 0.5ppm the best way to get it down is to take FC to above its oxidisation level. That is normally sufficient to clear the water within a day or two without any further action required and FC levels allowed to subside back to normal. That level known as the shock point is dependant and is a percentage of the existing CYA level… so you need to know what that is. Any saltwater pool also needs chlorine to keep algea at bay. A saltwater generator (SWG) converts salt into a percentage of chlorine. Always round, effectiveness and cost wise.. it’s not really a great idea to use non chlorine shock. Patience is required and I know how difficult that is when your itching to use the pool!!! but I strongly advise you get one of those test kits first so you know exactly where you are with PH, CYA, FC and CC to start with… that’s got to be your base point… armed with that info you can shock the pool to the correct level with Sodium Hypoclorite. (Liquid Chlorine). Simply keep,it above shock point till the brown water becomes crystal again… which if there are no algea spores in there… shouldn’t take very long. I suggest you get the kit, obtain the readings and go from there! Any problems or unsure about anything then obviously get back to me with the results of those four readings.

  • Kim French

    I have an above ground pool and my levels are way off. Total hardness 1000 free chlorine 5/10 ph 8.4 total alkalinity 240 cyanuric acid 100. What can I do to fix these?

  • Dontay

    Kim… Wow! Sorry but the short answer I’m afraid is… other than start again not a lot! What sort of pool is it… concrete and tiled or vinyl lined? What sort of test kit do you use that’s given you those results? What is your volume of water? The major problems are your CYA and CH numbers IF they are in fact anywhere near accurate! TA and PH can be adjusted over a period of time… so not TOO much of a problem. I don’t understand the FC number can you clarify its level?

    The only way to get CH and CYA back to some semblance of normal is through water dilution. There is no chemical that can lower either of those parameters.

    CYA is a manufactured product so it’s not present in normal fill water. Drain away say 50% of your water volume and topping up with fresh… would also lower CYA by 50%. For the majority of climates except regularly very hot ones CYA should be somewhere between 30 and 40 ppm. With your figure of 100ppm that would mean replacing around two thirds of your water.

    However your CH which you think is 1000 presents an even worse problem… since normal fill water DOES have calcium present. Levels vary across the country but that obviously means it’s more of a problem than just removing some and replacing an equal volume of fresh water. Vinyl liner pools don’t actually need any calcium but it’s not a problem if they do… tiled pools DO need some to prevent the water grabbing what likes out the grout/plaster lines… but in either case CH should never exceed 350ppm to prevent hard scale forming in the pipes and staining of pool surfaces. I DO question the accuracy of those results though!

  • Kim French

    It is an intex above ground vinyl liner pool. It is 22 ft round by 52 inches deep. I am using an HTC testing kit. Have drained 1/4 of the water and refilled. We have well water.

  • Dontay

    Kim… I’m not familiar with the HTC test kit so I can’t offer an opinion on its accuracy. What i can say is if it isn’t a FAS DPD drop count kit then it’s accuracy is highly suspect. There is no other type of kit that can give you the accuracy that you need to have. All CYA tests measure the water turbity. Turbity tests no matter which kit you use have margin of error ((MoE). The CYA test with the least MoE is known as the ‘ disappearing dot’ test. The MoE for that test is around plus or minus 7ppm. The FAS DPD type kits have the disappearing dot test for the CYA parameter. All other types of turbity tests can have a MoE of around 20ppm!!!! If you live in an exceptionally hot part of the country then your CYA can be set to around 50ppm but It’s really a personal judgement call. CYA dramatically protects chlorine from being burnt out of the water by UV light. The hotter the sun then the higher the CYA level will need to be. The disadvantage to CYA is that it also restricts chlorines disinfectant abilities. Because of that the FC levels have to be set correspondingly higher. It’s a balance or trade off between the sun burning off the FC so you need to add more chlorine…. and the CYA restricting disinfectant ability so you you need more chlorine to keep it at a higher level! If your CYA result at 100ppm IS correct then your absolute minimum FC level should not drop below 7ppm and you should daily target dose to 12ppm to allow for a 24 hourly chlorine loss and ensure it doesn’t drop below 7ppm. If CYA is brought down to 50 ppm then minimum FC is only 4ppm, FC target dose is 6ppm and chlorine oxidisation point is 24ppm. In percentage terms it’s 7.5 %. 16% and 40% of the CYA levels.

    To be honest, I think this all a bit academical for you at the moment. Your CH result IF it is to believed… is astronomically high! The only way to lower CH is to drain water away and replace it. But in tandem with that is the expense involved with reducing the TA with acid (which is what you would need to do) and the complications that acid also has on PH. Acid slowly drives down TA but it also takes down PH. Your PH DOES need to come down but not by an awful lot… 7.6-7.8 is fine. The only way to get TA down from your figure is to spend most of the season continually dosing the water with acid. You can’t do it quickly because PH will also keep dropping. That means lowering TA until PH gets down to 7.2 which is the minimum you should allow PH to drop to…. you then have to get PH back to 7.8 so you can then add more acid in your continuing efforts to get TA down to its eventual normal range (80ppm -120ppm) again causing PH to drop!!! You will probably end up doing that several times throughout the season! You CAN higher PH without resorting to chemicals but it’s a very long job and you have to ask yourself if this is all worth the effort or would it be more comical and lots less time consuming to just replace the water. It seems to me that it all depends on exactly what your well water levels are to start with. If it’s naturally extremely high in calcium then there is not much you can do except live with it. But levels of calcium above 350ppm usually also mean living with rather cloudy water… quite apart from any scale or staining problems. I think the best thing to do for starters is to get your well water tested for calcium if you haven’t already done so… also TA and PH. I would also suggest you get an FAS DPD kit to do it with so your sure of accurate info. You’ll need to go online to purchase one, most pool stores don’t sell them… but the costs are around $80 for a comprehensive test kit such as the Taylor K 2006 kit. If your well water also has the numbers you have reported then you obviously CAN do something about CYA even though it may mean replacing more water… and although it will be a very long and costly job it IS possible to also do something about TA and PH. If your well water has CH at 1000ppm all you can do is live with it… not much alternative I’m afraid.

  • Dianne Thomes

    I may just need to change the way I test. Never thought much of test strips anyway (just cheaper). Today my pool is very clear but still tinged brownish orange. I’m certain it’ll be clear by the weekend. I remember being at this point last spring. Just had to get past the cloudy point.
    Last question, how do I know if the titanium plates are bad in the Salt water generator I just bought it last year but it doesn’t seem like the chlorine level is rising very quickly. I typically ran it 4 hours a day last summer. (Minnesota has about a 4 month long summer ?). Have a cool day!

  • Dontay

    Hi Dianne… hopefully your right and your lovely pool will come clear. Obviously I agree you should get completely away from the test strips. There are loads of different kits available, some have tablet test reagents, some have liquid test reagent with a small hand held analyser… some of those are vary expensive indeed. Unfortunately and regardless of the makers claims for them, they become increasingly and more widely inaccurate at higher levels of FC. They all rely (one way another) on trying to determine slight differences in the water samples density (given by the depth of colour) none of them can do it with any real degree of accuracy. The problem with colour density kits is that slight differences can lead to large degrees of inaccuracy in the ppm stakes… giving a false indication of what the truth is. Particularly for FC the higher the ppm you have to go to if you ever have a problem and have to go to shock point… the more inaccurate these kits become. Most digital analyser type kits will not even give a read out for FC over 10ppm… their digital display screen simply reads ‘high’. Not much good when it’s so important to know when your shock point is. The tablet kits which rely on your own eyes to discriminate between slight differences in shading are even worse… if FC is at high levels the chlorine actually bleaches the water sample colour out of the sample, an effect known (obviously!) as ‘bleach out interference) As for test strips don’t even bother… the little pads are simply impregnated with cheap test reagents which gets them to change colour. All Test reagents have a ‘use by date’ (usually a couple of years from date of manufacture) and to maximise that they need to be stored in a cool dark place. Test strips don’t let you know what the use by date is because they are made in their zillions and shipped all over the planet… by the time you come to use them they can be years out of date and have spent most of their lives hanging from brightly lit nice warm shop shelve. NOT that they are any good when they’r fresh! FAS DPD kits do not suffer from any of those problems they have two test levels depending on how accurate you want to be… 0.5ppm or 0.2ppm. They also give an unmistakable CLEAR water result… you add one reagent to change the colour and then add drops of a another chemical from a droplet bottle until the sample changes from coloured to clear… you count as you go till the sample comes clear. The number of drops to clear water indicates your result. No colour or water density difference required! Easy to use and a comparatively very inexpensive way of obtaining accurate info that you can rely on.

    If your SWG cell is only a year old then it should be good. SWG’s let you set the percentage of chlorine you want… the only way to prove FC is going to the level you want it is via a water test. How fast it gets there could be dependant on number of things like how much water you need to get chlorinated, how effective your circulation from the pump is… but the most obvious is your chlorine protection!… CYA! In noonday sun an outside pool with zero CYA will lose 3ppm’s worth of FC in under 2 hours. It will hardly have the chance to do what it’s suppose to do and disinfect your pool before the sun grabbs it off you! If your CYA level is lower than suits your particular air temps then pretty much the same will happen. No pool, whatever the ambient temp should have less than 30ppm. 35ppm is better and if your air temps regularly exceed over 90f then go a bit higher… and because of the margins of error in any CYA test it’s better to ASSUME that it’s a bit higher even than the test result gives you and set your FC minimum level accordingly. With CYA at 30ppm your minimum FC level to stay safe and sanitised is 2.2ppm. (7.5% of CYA) If CYA is 40ppm then your minimum FC level to stay safe and sanitised is 3ppm. (7.5% of CYA) With CYA at 50ppm your minimum FC level is 4ppm (7.5% of CYA) Once again… get a ‘proper’ kit and test your CYA properly so you KNOW what it is… would be my first advice! Your pool will love you back if you do that :) One thing you must not do is try to do any super chlorination exercises using the SWG… you WILL help deteriate the cell if you do that, you’ll risk cutting its expected lifetime in half! Wish you well Dianne and hope you have a great summer in your pool.

  • Kim French

    It is an HTH kit. Thank you for your help. I will buy a good drop test kit.

  • Dontay

    Kim… Your welcome. Hope things work out OK for you. I said that there are other ways to increase PH levels if and when they drop whist trying to get TA levels down without resorting to chemicals. If you DO go down that route you need to be aware that PH increaser, which is bicarbonate of soda can also increase TA. The opposite of what you will be trying to do. It’s a vicious circle! To avoid that there are various means of increasing PH without also increasing TA. PH slowly rises due to disturbance of the water surface, heavy and prolonged rainfall, heavy bather load… lots of kids slashing around etc. You can also artificially disrupt the water surface by using a hose pipe with loads of holes punched in it, weighted and laid around under the surface and connected to an air compressor. The bubbles created will over time increase PH. Another way is to connect ordinary sink waste pipe to the return jets if you have those sort of returns. Simply unscrew the nozzles from the side of the pool wall, cut a couple of around 4 foot lengths of pipe and using normal waste connection fittings ( the threads are normally comparable with pool return threads… and you can form a couple of fountains! Anything that you can think of that will disturb the water surface will help PH to rise without using PH increaser.

    Be aware also that neither increasers or decreasers react quickly. It’s normal to dose the pool with the recommended amount of powder, diluted in warm or hot water, poured very slowly around the perimeter and then wait for 36-48 hours before testing to see what the results were. It can take that long to fully react in the water and give you an accurate test result. Only then should you dose again. It’s particularly important to do that when lowering TA because it gives PH a chance to recover naturally… which it may well do even over only a couple of days. You DO have some leeway because you need to get PH down anyway… but even so you maybe in for a season long job. But don’t let PH drop below 7.2 or the water will become very acidic. The FULL PH scale runs from 1 (acid) to 14 (base)… 7 is neutral… and there is one hundred times difference between each point on the scale. (7.9 is one hundred times more alkaline than 7.8… and so 7.1 is one hundred times more acidic than 7.2) Human membranes prefer PH to be on the alkaline side of neutral to avoid irritation… pool water PH has been found to cause least irritation problems for skin and eyes etc. when between 7.4 and 7.8. With PH over 7.8… FC’s percentage of effectiveness is reduced and weakens which can cause Chloromines (CC) to rise… that can lead to cloudy water and also opens the door to algea spores. As low as 7.2 IS safe for bathers but their is a high risk of irritation problems to anyone who has sensitive skin issues. 7.6 to 7.8 is the optimum. 7.7 gives some leeway for PH to rise or fall. PH very often recovers quite naturally over a couple of days… so minor rise/fall changes in PH are not normally a problem.

    Your CYA needs to come well down first… if you don’t keep FC to at least the correct minimum level (7ppm) to cope with your CYA at 100ppm (if that is anywhere near correct) then chlorines disinfection ability will come to almost a complete halt… a condition that is well known as chlorine block. Hopefully your fill water isn’t so high in the levels as they seem to be and by water dilution to get CYA down… you may also go along way towards sorting the other high levels.

    Best of luck Kim.

  • Melissa Weaver

    I have an above ground 30 foot pool, 25,000 gallons and I have been fighting a green pool for over a month now!! I now have it to blue but very cloudy!! I can’t see the bottom. I took a water sample in to the pool store for testing and I am balanced perfectly!! (finally) They sent me home with a bottle of clarifier to pour in and I did. I am still just as cloudy! What do you think should be my next step? Any help would be appreciated.

  • Dontay

    Hi Melissa… there can be several reasons for cloudy water but if your water was green to start with there is only one reason for you… you have algae! If you have been fighting to clear it up for over a month then you have not been fighting it in the correct way… and if it is still cloudy (although not now green) you have not yet succeeded in killing all the algea spores in the water. The pool store should not have sold you clarifier because (as you have discovered) it doesn’t work against algae! I’m afraid you really shouldn’t be relying on pool stores testing your water samples either. Pool store tests are notoriously inaccurate and to completely eliminate algae you need to have good quality and very accurate info from the water. You have been ‘Pool Stored’… your not alone … hundreds of other folk have too. Pool stores are only experts at selling you chemicals, either some you don’t need (like clarifier!!!) or the wrong type and giving bad advice based on their inaccurate tests but also through ignorance of correct pool care procedures.

    There is only one way to COMPLETELY clear a contaminated pool… and that requires you to raise your FC to ABOVE your chlorines oxidisation point (shock point) AND keep it there until your water is visually crystal clear. (there are then 2 final simple tests that you have do). Chlorines oxidisation point is based on what your existing CYA level is. So you need to know what your CYA level is in ppm’s – you need to know exactly what your FC is ppm’s at all times during shock proccedure – you need to know when you have exceeded your chlorines oxidisation point – you need to know when it’s about to drop through that oxidisation point. To be able to keep FC above shock point you have to test every 2 – 4 hours AND keep adding chlorine to ensure it doesn’t drop below shock point. The answer to ALL that is to buy your own test kit.

    There is ONLY one test kit that can accurately test for FC at shock point level… an FAS DPD kit. ALL other types of kit… including pool store own kits!!!!… will give inaccurate and unreliable information and is why folk end up trying to clear a contaminated pool for over a month and then find they are back where they started a few weeks later! From very seriously deep green it should take no more than a week in most circumstances if the correct proceedure is carried out. You ARE part the way there but unless you now start doing things in the correct way, the algae will recover – start multiplying again – and you will be back where you were very soon. Unfortunately there is no such thing as a ‘partial’ shockdose. The pool stores love to have their customers think there is!

    SO… first things first! FAS DPD kits are very simple kits, the most accurate you can buy and relatively inexpensive. In short, medium and long term one of those will save you hundreds $$$. The majority of pool stores don’t stock them but they are available online. Google FAS DPD test kits and you will find them Taylor Technologies and LaMotte are the most commonly used ones but there are other makers too. The Taylor K 2006 kit costs around $80… you may find it considerably lower, but I am not here to advertise any particular makers kit… any comprehensive FAS DPD kit such as Taylor’s will do the job.

    Once you have obtained a kit you will need first of all to carry out what is known as the ‘disappearing dot’ cyanuric acid (CYA) test. That will establish what level your shock point will be. Shock point (chlorines oxidisation point) is 40% above your CYA test result. Next test for PH and ensure it’s 7.8 or below (if IS higher than 7.8 then you will to lower it to between 7.4 and 7.8 using PH decreaser (acid) before you can start shock proccedure) Your existing CYA level must NOT be above 50ppm. If it is you will also need to lower it before starting shock procedure. The only way to lower CYA is through water dilution, there is no chemical that can do it for you. Normal ‘fill’ water does not contain CYA… so for example: if you drain away 50% of your water and replace it with fresh… then you will also lower your CYA level by 50%.

    Subject to that being all good you can now start shock proceedure.

    Raise FC to at LEAST 5ppm ABOVE your shock point. (The shock point is the MINMUM level you have to go to)

    Now you have to KEEP it above shock point. Chlorine is itself consumed by its job of gobbling up algae! That starts immediately the chlorine hits the water and happens VERY quickly. It is quite common for FC to drop by 5ppm in 2 – 4 hours. You MUST not let FC drop through your shock point… that’s why you go well above shock point to start with and you will need to test every 2 – 4 hours… adding more chlorine as required to ensure you DONT drop through that trap door. Eventually your chlorine demand will slow down, it will take much longer than 2 -4 hours to approach shock point and it will take increasingly les chlorine to keep above. Whilst this is going on you will notice your water is gradually clearing up! IT can take a two or 3 days from where you are now with cloudy water… but it maybe a bit quicker for you… it depends on the level of contamination.

    On the day you get to a TOTALY crystal clear water state you STILL need to maintain FC at or above shock point until dusk of that day. You then need to do an OCLT (Overnight Chlorine Loss test)

    At dusk, with NO sun on the water… do a FC test (it should still be at or above shock point!) Note the result. Turn the pump off and leave it off overnight . Add no more chlorine! The next morning BEFORE any sun on the water…(you may have to re-set your alarm clock!) test FC again. If FC overnight demand (chlorine loss) has been 1ppm or less you have passed the first part of OCLT. If you fail that test you need to ensure FC is back above shock point and keep going and do the same again that evening. If the demand HAS been 1ppm or less then you can do the the last test. Test TC. providing your CC is 0.5 ppm (1drop in the FAS DPD test) or less (no change of colour indicates zero CC) then you have completed eradication algae from the pool. If you fail the CC test keep going again until you you DO pass.

    There are 3 main types of chlorine: Stabilised (which means it contains CYA) which is in either powderd form of tablets/pucks. It should NEVER be used because the CHA levels just keep on rising. High CYA levels can bring chlorines disinfection abilities to almost a complete halt. The consequences are usually green pools! Next up is Calcium Hypoclorite which comes in powdered form and which the makers love to call “shock’ or some great sounding name such as ‘super fast shock wave’ (it’s actually no such thing) It’s Calcium Hypochlorite and if you use too much of it you can cause further problems because levels of CH (calcium hardness over 350ppm is one of those other reasons that can give you cloudy water!

    Both the CYA and calcium levels can only be lowered by water dilution!

    There is ONLY one ‘sort’ of chlorine you should use… just as a routine but especially when going to shock point! LIQUID chlorine. SODIUM Hypochlorite! All pool stores sell it.

    To discover how much liquid you need to get to a given level the the most accurate way is to test your FC level and then pour say 4 pints in the pool. (You dose liquid with the circulation running… by slowly pouring evenly divided into the return streams or slowly trickling around the perimeter).
    30 minutes after adding the liquid you test FC again to see how much FC has risen. From that info you can determine the amount required to reach around 5ppm more than your shock point. In 25,000 gall normal healthy pool I would expect 2 pints to give an FC rise of roughly 1.5 – 2ppm.

    There is one other point I would make. Shockdosing is NOT a preventative exercise… if it is done correctly it’s a complete cure and if MINMUM levels of FC are kept ABOVE 7.5% of CYA then it’s unlikely you will ever have a problem with algae ever again! It ‘prevents’ nothing… so regular shockdosing to some arbitrary timescale like it being the last Saturday in the month is NOT required. Keeping FC ABOVE 7.5% of CYA…. IS required!

    I suggest you get the kit… get your tests done to see where you are at the moment and go from there…. if you want to stick a couple of gallons of sodium hypo in the pool until the kit arrives then fine… it will expediate matters and might help prevent the water going backwards to green.

    Any problems or unsure of anything then come back and we’ll get you sorted.
    Best of luck.

  • Very helpful tips you have here! thanks for sharing! I just want to know, with all these products used to treat the water and clean the pool. Is it still safe especially to the environment? would like to know.

  • Heather Shoemake

    Have you tried priming your pump? My suction wasn’t strong either and I figured out I needed to prime it. Also make sure there’s no air in the line. If that doesn’t work try unscrewing the cap on your pump and letting it fill with water then tighten it back up. It won’t do right if my pump (I don’t know the proper name of it) isn’t full of water

  • Mr. Gregg

    I have a non-chlorine pool (Pristine Blue-copper based) and the water is cloudy. It was clear but I added soda ash to raise the PH. and then it clouded. I have been filtering the water 10 hours daily and changing the filter daily. Is this just a waiting game?

  • Dontay

    There can be several reasone for cloudy water including high PH which gives rise to Chloromines, CH over 350ppm incorrect chlorine levels which can also give rise to Chloromines, the first stages of algea contamination can appear as cloudy water.

    Pristine Blue should be used in conjunction with chlorine. Although P.B. can control algea it cannot kill bacteria quickly enough to protect bathers.

    Copper sulphate based products are used for the control of algae in swimming pools. Copper sulphate based products do not control microorganisms such as bacteria and viruses in swimming pool water. Only chlorine or bromine based products can provide this protection. To protect pool users, copper sulphate based products must be used in conjunction with chlorine or bromine sanitisers.

    If you have zero chlorine in your water it is likely that the cause MIGHT be high levels of Chloromines… if that is the case then the pool should NOT be used… high chlorine levels are dangerous to health…. but it is not possible to ACCURATLY diagnose cloudy water problems without knowing exactly what the test readings are for FC, TC, CC, TA, PH and CYA. These readings need to obtained via an FAS DPD test kit in order to ensure accurate results.

  • Alex Ardon

    I have a saltwater 22000 in ground pool. I use a sand filter.
    I have been fighting cloudy water for two weeks.
    Here is the last test result from the pool supply store:
    total Hardness 257
    Total Akilinity (TA)94
    Cyanuric Acid (CYA) 63
    Free Chlorine (FC) 0
    Total Chlorine (TC) 6.5
    PH. 7.3
    Minerals 4000
    Borates 46

    Please advise me on what to do.

  • Dontay

    Hi Alex, a saltwater pool is also a chlorine pool. Your CH, TA, are fine PH is a little low but not a problem. Your CYA and TC levels are the ones that are telling you something! But all that is assuming that your pool store results are anywhere near accurate! They invariably never are, take the same sample of water to three different stores and you will most likely get three widely differing results across the whole range of test parameters. It is definately not recommended that you rely on pool store results! There are never ending complaints of folk being ‘Pool Stored’! They like to sell you lots of chemicals but the number of pool owners still complaining of cloudy water are in their thousands!

    However if you chose to carry on with that, it’s your decision obviously.

    Your CYA is way too high and your TC is too. The difference between FC and TC gives you CC. Subtract FC (in your case zero) from TC (in your case 6.5) and your CC is 6.5ppm. CC (Combined Chlorine) in an outside pool should not be above 0.5ppm. CC is basicly a combination of ‘used up’ chlorine and dead bacteria. These compounds are called Chloromines. Chloromines are not only hazardous to health… they make the water cloudy! The reason they can rise is due to ineffective FC. FC becomes ineffective due to high CYA levels. At indeterminate CYA levels above 50ppm chlorines ability to disinfect the water can come to almost a complete halt… a condition known as chlorine lock. CYA protects chlorine from being lifted from the pool by UV light… sunshine! The hotter your normally expected summer temperatures the higher the CYA level has to be set to counter the effects of strong UV. No outside pool should have CYA at less than 30ppm. For moderate summers that rarely exceed the mid eighties 30 – 35ppm is fine. For hotter climates that regularly exceed 90f… 35 – 40ppm is fine. Climates that can exceed over 100f should have slightly higher levels. Your FC should be based on a percentage of whatever your specific CYA level is. Absolute minimum level of FC is 7.5% of CYA. It is safer to keep minimum FC levels slightly higher than that but for example: CYA at 30ppm then FC absolute minimum is FC at 2.2ppm. CYA at 40ppm then absolute minimum FC is 3ppm. It’s best to stay at least another 0.5ppm above minimum.

    Shock point (where chlorine oxidisation occurrs) is 40% of CYA. With CYA at 30ppm then FC will oxidise and shock the water at 12ppm. With CYA at 40ppm then chlorine (FC) will oxidise and shock the water at 16ppm.

    High CC levels are not normally a problem for outside pools and easily kept under 0.5ppm by correct levels of (effective!!!) chlorine and also by UV which breaks down the compounds and lifts them out of the water.

    Your level of compounds can only be broken down now by shocking the pool and raising your FC to above oxidisation level AND keeping ABOVE that MINIMUM shock level until water clears. With your CYA level given as 63ppm your MINIMUM shock point is approximately 25ppm… and as I will explain you have to go well above that minimum. That will take an awful lot of chlorine!

    Unfortunately their is no chemical that can lower CYA for you. The only way to lower CYA is by dilution. As CYA is not present in any fill water… if you drain off 50% of water and top it back up with fresh then you would also lower the CYA level by 50%.

    In order to save on chlorine costs and volumes I suggest you consider lowering your CYA before anything else.

    I must stress that FC MUST NOT drop below shock point. In order to achieve that it is important to go well past shock point.

    Shockdosing requires you to be available to continually monitor and test the water every 2 – 4 hours adding chlorine each time in order to ensure you do not drop down below shock point. It can take at least a couple of days from an opaque milky white coloured water or around 5 days from a green coloured pool. Chlorine is itself consumed by the job it does in disinfecting the water and breaking down Chloromines. With contaminated water it will drop by around 4 – 5 ppm in under 4 hours. Eventually chlorine demand slows down, it takes longer to drop towards shock level and increasingly smaller additions of chlorine are needed to keep it above shock level. As this procedure develops you will notice the water becoming clearer and clearer until it’s crystal clear.

    High CYA levels are usually caused by using stabilised chlorine products… this leads to incorrect minimum FC levels. Every-time stabilised chlorine is added to a pool there is an increase in CYA… CYA doesn’t go anywhere… it just keeps rising.

    Chlorine products with calcium give the same problem. Calcium Hypochlorite which the makers like to call ‘shock’ or give fancy names like super-fast shockwave (there is NO such thing, shocking the pool is a procedure… not a product) Calcium Hardness (CH) should never exceed 350ppm.. the result of doing that is staining of underwater pool surfaces, hard scaling in the pipes… and cloudy water! Using Calcium hypochlorite products can send CH soaring.

    Calcium levels can also only be reduced by dilution… no chemical can do for you. But unlike CYA… calcium IS present in normal fill water… so reduction is more problematical. However your level seems to be well under the limits… so fine!

    There is only one chlorine product you should use in order to avoid increasing cyanuric acid or calcium levels… that is liquid chlorine. It’s called SODIUM hypochlorite. All pool stores stock it. Chlorine is bleach, no-matter if it’s in powder, tablet/puck or liquid form. Sodium hypochlorite adds a small amount of salt. It would probably take around 4 pints of liquid (which should be slowly poured into the return streams) to raise FC by 2ppm in 22,000 galls.

    If you choose to shock your pool correctly you should fist of take the time to purchase an FAS DPD test kit. Most store do not sell them but available online. Google FAS DPD test kit and you will find them. The most commonly used ones are made by Taylor Industries and LaMotte but any FAS DPD test kit will give you the accurate results you will need to establish both your correct CYA level and from that you can establish your correct shock point. The Taylor K 2006 FAS DPD test kit retails at around $80. I recommend you obtain one, they are easy to use, come with full instructions and tests for all normal swim pool parameters. They are also the most accurate kits available… far more accurate than pool store tests! Borates are an individual choice… if you like Borates then fine.

    One thing folk should not do is try to use the SWG for any form of super chlorination exercise… you will chop the expected lifetime of the cell in half.

  • Jm Andrew

    I have a similar pool….did you get your water clear? If so, what did you do?

  • Melissa Weaver

    I have finally gotten it fairly clear!! I can at least see the bottom. I have inground steps in my pool and had not taken them out. I found them to be full of mustard algae. I think that was part of my problem. I took the steps out and shocked again with a mustard treatment and a double turbo shock (calcium hypochlorite). We vaccummed the next day but still cloudy. I ended up floccuing which I didn’t want to do but it worked. I am still not crystal clear but from what I have read some of the cloudiness can be cause from the shock so I am going to hold out a few more days before adding any more chemicals except chlorine and see if that will do it. Good luck and I hope it helps.

  • Jm Andrew

    Thanks, I’ll have to check my steps too.

  • Dontay

    There can be several reasone for cloudy water including high PH which gives rise to Chloromines, CH over 350ppm. incorrect chlorine levels can also give rise to Chloromines, the first stages of algea contamination can appear as cloudy water.

    Pristine Blue should be used in conjunction with chlorine. Although P.B. can control algea it cannot kill bacteria quickly enough to protect bathers.

    Copper sulphate based products are used for the control of algae in swimming pools. Copper sulphate based products do not control microorganisms such as bacteria and viruses in swimming pool water. Only chlorine or bromine based products can provide this protection. To protect pool users, copper sulphate based products must be used in conjunction with chlorine or bromine sanitisers.

    If you have zero chlorine in your water it is likely that the cause MIGHT be high levels of Chloromines… if that is the case then the pool should NOT be used… high Chloromine levels are dangerous to health…. but it is not possible to ACCURATLY diagnose cloudy water problems without knowing exactly what the test readings are for FC, TC, CC, TA, PH and CYA. These readings need to obtained via an FAS DPD test kit in order to ensure accurate results.

  • Sarah Schwab

    I gave an in ground diving pool and it is very cloudy. There is no algae as I shocked it with 3 pds last night. I used a clarifiEric but nothing seems to be clearing it. Help please..I do know that the chlorine level is too high so I did backwash and filled with fresh water. Thanks

  • Dontay

    Sarah… there can be several causes for cloudy water but to get to an accurate diagnosis you need to provide specific info or you will end up blundering around in the dark… spending lots of money on chemicals you most likely do not need… and STILL have ‘cloudy water’

    The most common causes of cloudy are either Chloromines (which are the compounds in Combined Chlorine (CC)) OR algae spores OR calcium hardness (CH) levels above 350ppm.

    High levels of Chloromines are normally caused through ineffective minimum chlorine levels in relation to the Cyanuric Acid (CYA) levels… OR chlorine levels which are too high in relation to the CYA levels… OR PH levels over 7.8. As with Chloromines (CC)…. algae spores can also enter the water and make it cloudy prior to turning green if the Chlorine (FC) levels are either too high or too low in relation to the CYA level.

    Opaque milky white cloudy water is also the normal after effect of STARTING to kill algae… and if you do not complete the shockdose process it will stay cloudy and eventually turn green.

    Combined Chlorine (CC) is basicly a combination of ‘used up’ chlorine and ‘dead’ bacteria… these compounds are Chlorimines…. the stuff chlorine has destroyed!

    Chloromines are dangerous to health and CC should not rise 0.5ppm. In a normal outside healthy body of water it will not do so. Chloromines are broken down and lifted from the water by regular exposure to sunlight and correct levels of chlorine.

    Shockdosing a pool is a procedure NOT a product… as much as the pool chemical industry would like you to believe otherwise! Chlorine products labled ‘shock’ are nothing of the sort… look at the label properly and you will see Calcium Hypochlorite. These products used in the quantities that are required to raise your FC to shockdose ‘point’ can send your calcium hardness levels over 350ppm and one of the the result is continually cloudy water! The only way to lower calcium levels is by way of water dilution… but bear in mind normal fill water also contains calcium… in the case of well water… sometimes very high levels of it!

    Shockdose ‘Point’ is a specific level that you have to raise your chlorine level up to in order to promote a chemical reaction where chlorine oxidises and begins to breakdown high levels of Chloromines (above 0.5ppm!!!) AND/OR kill algae spores!!! VERY importantly that oxidisation level is a percentage of whatever level of your specific CYA (stabiliser) level is! ALSO very importantly that minimum shock point level has to be MAINTAINED UNTILL the water turns cystal clear again. Failure to keep FC at or above oxidisation level until you get back to crystal clear water means you will see the water slip backward.

    Knowing what your CYA level is vital! You need that in order to determine your shock point level.

    Minimum FC should be kept to 7.5% of whatever your CYA is. Shock point… where chlorines oxidisation takes place… is 40% of whatever your CYA level is.

    Because chlorine is very rapidly consumed by whatever it’s required to do… it means raising FC to well ABOVE your shock point! In order to ensure that happens you need to test the FC levels every 2 – 4 hours… adding chlorine as necessary to stay above shock point. That means you have to have an accurate test kit and YOU have to there to use it and stick more chlorine in your diving pool!

    ALL outside pools should have a minimum of 30ppm of CYA in order to protect chlorines loss to UV light. (Sunshine!) A pool with zero CYA can expect to lose around 3ppm of FC hot noon day sunshine in under 4 hours! In very hot climates CYA levels will need to be higher in order to protect chlorines loss to the sun. However the higher the CYA level then the higher the FC has to be… because in an outside pool FC levels are a percentage of prevailing CYA levels rather than just keeping FC to recommended 1 -3ppm. THAT only apples to indoor pools… but the industry doesn’t want you to know that! The ‘industry’ prefers you to buy chemicals! Products such as clarifier and|or flocks do NOT work against Chloromines OR algae spores and they are NOT needed!

    With CYA at 30ppm… the absolute minimum target level for FC is 2.2ppm. The shock point (chlorines oxidisation level) is 12ppm.

    With CYA at 40ppm the absolute minimum target level is FC at 3ppm… and shock point is 12ppm.

    In the case of minimum targets it is safer to keep FC 0.5 to 1ppm above those minimum target levels.

    CYA (even in the hottest of climates) should not exceed 50ppm. At indeterminate levels above 50ppm a condition known as chlorine block can occur. Chlorine… no matter how much you stick in the water does not work!

    There is only one way and one ‘type’ of test kit that will give you the accurate info you need to get to clear water… regardless of the causes of it. 1) test the water yourself and do not under any circumstances rely on pool store tests. 2) purchase an FAS DPD test kit. Pool stores don’t sell them OR use them because they want you to buy chemicals! FAS DPD kits are available on line… they dont have fancy names so Google FAS DPD test kit and you will find them. ALL these types of kit are good but the most commonly used ones are made by Taylor Technologies and LaMotte. To give you an idea of cost the Taylor K 2006 kit retails up to around $80… you may find it cheaper… but ALL FAS DPD kits will test for all normal water parameters including the all important CYA and FC ones. They also happen to be the most accurate kit you can buy!

    This is the water chemistry ‘science’ behind what happens to chlorine:

    You actually need very little chlorine in the water as an anti-bacterial agent and so keep CC under control in an outside pool… (that becomes more important in an indoor pool) but you DO need to keep FC at correct minimum levels to protect against algae in an outside pool. If you KEEP the correct levels, algae spores will not invade your water but once you let them in there is only one way to kill them.

    When you stick chlorine in the water a percentage is instantly converted to Hypochlorous Acid (HOCL). that’s the disinfecting agent in chlorine that we call Free Chlorine (FC). The percentage that’s created is dependant on the PH level. HOCL is a highly unstable molecule which dissipates rapidly in the presence of sunlight.

    Proper stabilisation of HOCL with CYA seriously slows the rate of dissipation by the sun without appreciably sacrificing oxidisation & disinfection activity. HOCL reacts with substances other than water to produce ammonia which in turn produces chloromines, this occurs in several stages with HOCL (FC) consumed at each stage.

    With FC kept at correct levels and the water exposed to sunlight for the equivalent of 2 days a week CC rarely becomes a problem… and UV sunlight is a very effective and free way to keep them under control! Anywhere between zero and 0.5 ppm is fine. ONLY when CC has got above 0.5 ppm do you have to shock to get them down. THAT it easily and quickly done… usually within a day or so.

    Algae is a different matter and unfotunately the most common and persistent problem.

    HOCL also easily dissociates into an ionised hypochlorite state called Hypochlorite Ion (OCI).

    The balance between HOCL and OCI is effected by PH levels. The higher the PH the less HOCL is present… and so FC is less effective. At a 7.2 PH roughly 66% is of chlorine is effective FC (HOCL) At PH 7.8… around 33% is effective FC ( but that’s fine!) we still need CYA’s ability to moderate it’s strenghth even its only 33% effective. BUT… If PH rises above 7.8 then immediatly get it down or the result will be cloudy water due to higher levels of Chloromines and possibly opening the door to algae.

    Now then…. CYA shields a percentage of HOCL from the sun by moderating it’s strength and also by ‘binding’ a percentage of it and holding it in reserve… that ‘held back’ proportion is released in direct proportion to the the amount of ‘unbound’ FC as it is consumed.

    IF you chlorinate to 3ppm in an outside un-stabilised pool… then in noonday sun that 3 ppm of FC a will be gone in well under 4 hours.. sometimes under 1.5 hours!… the vast majority of it taken out by the sun! So it’s vital to have CYA in an outside pool. BUT in an outside (regardless of size or volumes of water… FC is ALL about percentages!

    The higher the CYA level then the higher your FC level has to be in order to allow for that ‘bound up’ FC percentage. The hotter the sun the more intense the UV and the more rapidly the ‘unbound’ FC gets eaten up… so the more rapidly CYA ‘bound up’ FC also gets released and eaten up!

    SO… the hotter your normal ambient climate the higher you should have CYA to protect against loss and therefore the higher your FC level should be! It’s ALL about percentages! You need CYA…. but not too much of it! High levels of CYA above 50ppm can bring chlorines disinfectant activity to an almost complete stop!

    The FAS DPD type test kits show the total amount of FC… unbound and bound.

    Algae spores take a long time to die and if you leave even a couple left alive after shocking the water they will multiply again and you will be starting all over again!

    Keep FC above 40% of CYA UNTILL totaly crystal clear water is apparent.

    Then you need to do an OCLT. Overnight Chlorine Loss Test.

    At dusk test for FC. It should STILL be at or above oxidisation level!

    Note the result of the FC test and switch off the pump.

    Do not add anymore chlorine.

    Next morning BEFORE any of the Suns Ray’s have hit the pool, test FC again. If the results show the the overnight chlorine demand (chlorine LOSS) is 1ppm or less… the water has passed the first part of the OCLT.

    Now test for Total Chlorine (TC) The difference between TC and FC is CC. (Subtract FC from TC and what is left is CC!!!) if CC is 0.5ppm or less the water has passed OCLT and you have sucsefully completed shocking the pool and you can now allow chlorine levels to drop to normal over the following days. If either of those two test fail then you should return to keeping FC above shock point until OCLT is passed. Coplete shock procedures form a deep green pool to passing OCLT can take up to a week. From an opaque milky white situation it may only take a couple of days…it depends on the level of contamination but in all cases it is vital to keep FC above oxidisation level UNTILL OCLT is passed! Failure to do so will mean starting again within a few weeks! Just want the chemical makers and pool stores would like you to do!!! Shockdosing is a CURE…NOT a prevention exercise. It prevents nothing! Keeping FC levels above minimum Is the prevention! The is absolutely no requirement to shock dose to some abitary timescale such as doing it because it’s the last Saturday in the month! Keep the CYA/FC percentage ratios correct and it is unlikely you will ever shockdose again!

    ONLY use SODIUM Hypoclrite in your water… both as a routine daily dosage and vitally… as a shockdose. Sodium Hypoclorite is liquid chlorine… and all pool stores sell it. the only other thing it adds to your water is a small amount of salt. ALL other types of chlorine add either CYA or Calcium. The only way of lowering those is by pouring water away and topping up with fresh!