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.