Not only is cloudy pool water uninviting, but it could also be breeding dangerous bacteria or damaging your pool. So to avoid expensive repairs and illnesses, you need to figure out the cause of a cloudy pool before you can fix it.
What Causes Cloudy Pool Water?
Usually, it takes some time for your pool water to turn cloudy. Some water problems can cause noticeable cloudiness to occur seemingly overnight. So what the heck happened?
1. Low Sanitizer Levels
A lack of chlorine, bromine, or other sanitizers in your water can lead to bacteria growth and increased stress on your filter. You might have low sanitizer levels because…
- Natural debris (leaves) use up your sanitizer attacking it. If the debris isn’t removed quickly by you or your filter, it’ll gobble up your sanitizer.
- Sweat, sunscreen, beauty products, and even urine deplete chlorine.]
- The sun’s ultraviolet rays break apart the sanitizing hypochlorite ions created when you add chlorine to your pool, causing them to evaporate into the air around your pool.
So while the chemicals are busy attacking a pile of rotting leaves on the floor of your pool, they’re less effective at quickly killing hazardous pathogens and bacteria, such as E. coli, making your cloudy pool water ugly and dangerous.
2. Filtration Problems
Problems with your pool’s circulation system are a leading cause of cloudy, hazardous pool water. It’s mostly preventable by keeping the circulation system healthy. Make sure…
- Your filter isn’t clogged.
- Your pump isn’t dying.
- Your filter media (sand, DE, or cartridge) doesn’t need to be replaced. Watch how to change your filter sand.
- And you’re running your filtration system for at least 8 to 12 hours a day.
Your pool circulation system can fail you as it gets older, or it can be damaged by wonky chemical levels or neglect. When your filter can’t remove contaminants as well as it should, you get cloudy pool water, and probably a handful of other gross water problems.
3. Poor Water Chemistry
High pH and Alkalinity can form scale on pool surfaces and inside plumbing while making it more difficult for your sanitizer to work. This can also cause filtration problems, bacteria growth, and cloudiness.
And if chlorine levels are wonky, you can also end up with a lot of chloramines—the byproduct of chlorine sanitizing—which can be irritating and even corrosive. This is reason enough to learn how to clear cloudy pool water.
If you’re tired of cloudy water and just want an unbiased and reliable guide to never deal with this problem again, invest in The Pool Care Handbook and Video course today!
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How to Clear Up Cloudy Pool Water
Ready to get your pool water back to its former crystal clear glory? It’ll take a little hard work, but you’ve got this—and we’ve got you!
1. Give Your Pool a Deep Clean
Before you do anything else, start by giving your pool a good scrub down. Remove large debris with a heavy-duty skimmer. Brush your walls well with a stiff pool brush, then vacuum.
If you think you’ve got an algae problem, vacuum to waste. If you have pool algae, you should deal with that first. Learn how to get rid of pool algae here. And learn how to vacuum your pool to waste here.
2. Shock Your Pool At Night
To get rid of all the gross and dangerous crud in your cloudy pool water, shock your pool. This mega-dose of chlorine (or non-chlorine shock for pools that use other sanitizers) will eliminate cloudiness caused by bacteria, organic contaminants, and algae.
Note: If the cloudy water in your pool is due to pool algae, you’ll have to double or triple shock depending on the type of algae that’s invaded your pool. And always shock your pool at dusk or night for maximum effectiveness. Read more about that here.
Why is my pool cloudy after shocking?
Adding pool shock to an otherwise perfectly clean and balanced pool can even cause temporary cloudiness. But if you add the proper dose of shock, it can clear your pool right away if your pool water filtration and circulation are working properly.
3. Filter Your Pool Water 24/7
Okay, you don’t actually need to filter your pool water indefinitely. Eight hours per day is enough for most pool pumps to turn over the average backyard pool. But you’ll definitely want to deep clean or replace your filter before running it.
Do this after you shock the pool to be sure the extra sanitizer is rinsed through your circulation system and filter, and clean water is distributed.
4. Use Your Bottom Drains
The main skimmer is at the surface of your pool. It can’t get to the debris at the bottom. Even some pool vacuums can’t get quite all the sediment away. If you turn on the bottom drains in your inground pool, you’ll be sucking that sediment straight to your filter.
Do you have an above ground pool that doesn’t have bottom drains? Use this trick: Hook up your manual vacuum cleaner and center it at the bottom of your pool. Then turn it upside down. Your filter will pull water from the bottom of your pool using the vacuum head, then release the filtered water through the return jet.
5. Balance Your Chemistry
Once you’re sure your water is as clean as it can be, test it or take a sample to your local pool store. Adjust chemicals as needed until your water is balanced. Use chlorine stabilizer—also called cyanuric acid—to protect your chlorine levels.
This digital pool and hot tub water test kit checks for Free Chlorine, Total Chlorine, Bromine, PH, Alkalinity, Calcium Hardness, and Cyanuric Acid.
6. Floc Your Pool
If you’re in a hurry and your cloudiness isn’t too bad, you can try using a pool flocculant. Once the floc does its job, all the suspended debris in your water will sink to the bottom. Vacuum it out (to waste), top off and balance your water, and you’re all set to use your pool.
Pool floc binds particles (and dead algae) that are making your water cloudy together and sinks to the bottom of your pool so you can easily vacuum out the cloudy mess.
7. Use Pool Water Clarifier
You can make this pool additive a part of your weekly water care routine as a preventive measure. Water clarifiers won’t address any of the more serious problems that may cause a cloudy pool, but it will help keep your otherwise well-maintained pool water looking great by coagulating debris making it easier for your filter to catch.
Your filter can clear a cloudy pool. But your filter needs help picking up particles that are too small. A clarifier binds these particles together, so your filter can remove them easier.
How Long Does it Take For a Cloudy Pool to Clear?
Depending on how cloudy your water is, it may take 2-3 days for your water to clear. Just make sure you run your filter 24/7, keep your water chemistry balanced, and add the proper amount of water clarifier every other day until it’s clear.
What happens if you swim in a cloudy pool?
It will actually help clear the water faster! Why? Because swimming improves water circulation. However, cloudy water presents a risk of drowning. So before you swim, make sure you can at least see the bottom of your pool, according to the CDC.
Stop Cloudy Pool Water Before It Starts
Clearing up your pool isn’t a massive undertaking, but depending on the problem it can cost you a bit in chemicals and elbow grease. But you’ll appreciate it when you leave the cloudy pool behind and dive back into sparkling water.
Make sure the only clouds you see are the ones in the sky. Weekly testing and balancing, skimming and vacuuming, basic filter maintenance, and regular shocking will keep your pool healthy and clear all season long.
Happy Swimming!
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