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Water Care Advice

How to Clear Cloudy Pool Water 

How to Clear Cloudy Pool Water

Cloudy pool water is a common but fixable problem. Many people deal with it and become frustrated because they might know what's causing the cloudiness. With the number of chemicals and variables that go into taking care of a pool, it can be challenging to return your pool to a clear, tranquil appearance. When a pool is cloudy, it often works against its primary use — swimming. Family and friends can be put off at the sight of the murky water.

With some basic knowledge about how a pool interacts with its environment and some strategies for preventing a cloudy pool, you can gain the confidence you need to keep your pool healthy and thriving. 

Why Does a Pool Get Cloudy?

A pool can get cloudy for numerous reasons. Sometimes this can be because of unbalanced chemical levels, the weather or a bad filter. When you take care of a pool, you should monitor the water and be aware of these elements. 

High or Low Chlorine Levels 

One of the most common explanations for cloudy pool water is too low or too high chlorine levels. Chlorine is necessary for any pool owner who wants to keep their water safe. The chemical disinfects your water, effectively eliminating bacteria and algae that could cause disease. A pool with a high chlorine content will appear almost opaque, and a pool with low chlorine levels will look cloudy as organisms grow. Too much chlorine can be dangerous for people swimming in your pool. 

Accurate measuring and caution will usually fix over-chlorinating your pool, but chlorine dilution often happens out of your control. A few factors can dilute your chlorine content: 

  • Rainfall: Excessive rainfall can break down chlorine and dilute it, making your pool more susceptible to bacteria. If you're in an area where storms occur frequently, this could be a reason why you're pool is often cloudy. 
  • Sunshine: Ultraviolet (UV) radiation is very effective at diluting chlorine. Constant, focused sunlight with a high UV index could leave your pool lacking chlorine and explain that cloudiness. 
  • Temperature: Warmer water is more accessible for bacteria to grow and thrive. If you keep your pool at a balmier temperature, chlorine may have a more challenging time keeping bacteria at bay for long periods. 
  • The number of people swimming: People bring their bacteria into the pool — the more people you have, the more your chlorine will dilute. 

High or Low Chlorine Levels

Excessive Calcium Content

Your pool's calcium content determines how hard your water is. Hard or soft water simply refers to the mineral levels in the tap water. Soft water will begin to erode your pool bottom and walls to get the calcium it needs. Hard water, or water with too much calcium, will turn your pool water cloudy and could start to clog filters. 


When you use pool shock solution to shock a pool, you add a certain amount of chlorine that essentially guarantees you kill off any lingering bacteria. Shocking is effective, but it also can leave your pool looking cloudy. This kind of cloudiness isn't necessarily a bad thing — it simply means that the chlorine is still dissipating. For safety, you should wait to swim until the pool looks clear again. 

Too Much Hydrogen

Hydrogen measures the acidity of your water. If the acidity is too high, the water may start corroding your pool by breaking apart materials and clouding your water. Water that isn't acidic enough — or basic — will impact chlorine levels and make the water appear cloudy. 

Ineffective Filter 

The filter is what keeps your pool clean, by circulating dirty water, cleaning it and returning it. When this stops working or clogs up, you can notice issues quickly. If your filter is older, it could be more liable for breaks or ineffectiveness. Your water won't get the treatment it needs, which will cause it to become murky. 

Is It Safe to Swim in a Cloudy Pool?

It's generally considered unsafe to swim in a cloudy pool because of the number of factors contributing to that cloudiness. A few reasons it could be a good idea to avoid swimming in a cloud pool include: 

  • Decreased visibility: Swimmers won't be able to see, and those watching for safety, including parents or lifeguards, will have a harder time identifying if a child is struggling to swim. Cloudy pools can also create an increase in collisions for swimmers, resulting in injuries. 
  • Risk of bacterial infection and disease: Cloudy water is often the sign of low chlorine levels, resulting in the growth of bacteria and disease-causing organisms. When you swim in a cloudy pool, you risk exposing yourself to these potentially harmful organisms.
  • Chlorine side effects: Too much chlorine can also pose serious issues. Exposure to too much chlorine can cause rashes, coughing, pain in the nose and throat and adversely affect asthma patients. 

A cloudy pool can take the fun out of swimming, so it is best to find and treat the cause of the cloudiness first. In some cases, you may need to wait an hour for chlorine to dissipate. In other cases, it may need a more extensive fix like a new filter or complete drainage. Whatever the reason, there are several strategies to reduce cloudiness in your pool. 

Is It Safe to Swim in a Cloudy Pool?

5 Methods for Clearing Cloudy Water

Now that you know the causes and dangers of your cloudy water, you could be looking for solutions to return it to a clearer state. WaterGuru has tips for how to fix a cloudy pool and get your water looking crystal clear. 

1. Correct Your Chlorine Levels 

Chlorine is often the cause of a cloudy pool, so you need to track the levels. An easy way is to test your pool for free chlorine. Free chlorine is chlorine that can kill bacteria, combined chlorine is the chlorine that has bonded with contaminants and total chlorine is the sum of these two. 

If your chlorine levels are too low, you could be letting harmful bacteria thrive in your pool. Shock your pool to kill these contaminants. If the chlorine level is too high, this could explain your cloudiness — let the chlorine dilute some more and see if it goes away. Chlorine is the most typical issue that causes cloudiness, so you should check this first if you don't exactly know why the cloudiness is happening. It's also just good safety sense — low and high chlorine levels have effects that can harm swimmers. 

Because sunshine can deplete chlorine levels, consider where your pool is in relation to the sun. Is the sun consistently hitting your pool's surface, or do you have some trees and buildings blocking it? If your pool is in the direct line of sunlight, consider covering your pool when it's not in use. You could also purchase a chlorine stabilizer to keep your chlorine levels consistent. 

After the colder months, the water will often look extremely cloudy and even green when you first open your pool. This results from low chlorine levels, which has let bacteria and algae flourish in its absence. Shocking will usually kill this bacteria and return the water to its normal state.

2. Ensure Filter Is Working Properly 

Inspect your filter regularly to keep your pool clean. As a general rule, it's good to clean your filters at least about every six months. Also, make sure your filter is running long enough to circulate the pool water properly. For pools that get a lot of traffic, the filter should be going all the time to clean the water effectively. But for personal pools that don't get as much use, running the filter around eight hours a day will probably be okay. 

If the water begins to look cloudy, consider lengthening the filter's running time. Make sure the filter is not overly dirty, or else your pool will just be recycling filthy water — resulting in your cloudiness. If the filter is covered in green or brown filth, use a hose to spray it off. 

If the filter is clean, but you're still experiencing cloudiness, it could be a deeper problem — a broken valve or part. Inspect your filter for these issues to determine if you might need to call a service. 

3. Clean Your Pool Regularly 

Aside from chemical imbalances and bad filters, your pool could become cloudy from dirt that naturally falls into the water. If you have a lot of trees in the area or runoff from storms, your water could become murky. Small things like dirt, dust, pollen and bird droppings can accumulate in your pool, and chemical deposits from runoff will collect in the water. 

To alleviate this, clean your pool regularly. Clean your skimmers, use a net to scoop leaves out and examine any natural ways your pool could get contaminated with dirt. You can use vacuums and scrubbers to suck out any algae at the pool's bottom. Regular cleaning will help your pool stay clean and work with the filter to recycle better water. 

4. Test Your Water Frequently

It's good to test your pool every week. This will ensure many things — that your chlorine levels aren't getting too high, that the water isn't becoming too hard or soft and that the acidity stays at a reasonable level. Monitoring your levels won't necessarily fix all of your problems, but it's a great preventative measure that will give you the information to fix a problem if it does arise. You'll better understand why your pool is cloudy and what to do to fix it. 

Your pool's pH levels should stay around neutral — about 7.2- 7.8. The closer to 0 your pH levels are, the more acidic they will be, and as levels get closer to 14, your water will become gradually more basic. You'll need to add acid to keep the pH neutral for low levels, and for levels on the high side, you can use sodium carbonate to bring the acidity down. Stay in that neutral zone to keep your water clear. 

5. Use a Smart Pool Monitor 

Smart pool monitors are a great way to stay updated on your pool's water content. Instead of having to test your water every week manually, the smart pool monitor does it for you, often giving you a digital overview on your phone or computer of your water's pH levels. Smart pool monitors are great because they eliminate the time it takes to check your pool and let you live your life without having to worry about the content of your pool. 

5 Methods for Clearing Cloudy Water

Can Cloudy Water Come Back After You Clear It?

Cloudy water can come back after you clear it. Even if you think you've found the main culprit of the cloudiness and you think you've got it taken care of, the cloudiness can creep back in for another reason. It can be challenging to figure out the cause, especially after looking at all the factors that go into keeping a clean, clear pool. You might be overwhelmed by everything you have to keep in mind but the good news is that it doesn't all have to be put on your shoulders.

WaterGuru Can Help Keep Cloudy Water Away 

WaterGuru SENSE is a smart pool monitor that tests your water for you. You just put it in your skimmer and it tracks your pool's chemical levels, flow rates, water quality and temperature. 

SENSE pairs with your phone over Wi-Fi so you can get a fully digitized version of your water quality, giving you speedy access to all the valuable information about your pool. SENSE gives you an exclusive app where you can easily get all of your information. The app does more than just give you your water tests — it provides you with expert tips and advice on how to take care of your pool. 

WaterGuru works better than other products on the market. Other smart pool monitors sit on the pool's surface and only get tests of the water sitting on the very top of your pool. WaterGuru SENSE goes right in your skimmer, consistently reading pump flow for the most accurate readings. You'll also be able to easily retrieve your monitor from the skimmer, so you can keep it safe and secure and access it whenever you need to. 

SENSE measures free chlorine and pH directly instead of getting approximations, giving you the best possible reading of your pool's water content. WaterGuru SENSE will give you everything you need to gain the confidence to prevent cloudiness in your pool and keep the water looking crystal clear. 

Contact WaterGuru Today 

For an easier pool testing process, get WaterGuru SENSE. You'll have all the information you need in the palm of your hand. From convenience to accuracy, SENSE is one of the best smart pool monitors on the market. Buy yours today! 

Contact WaterGuru Today

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