As pool owners, we all have to deal with cloudy pool water at some point. Determining the cause of the cloudiness is the first step in remedying the situation. Cloudy pool water can be caused by improper levels of chlorine, pH and alkalinity imbalance, broken or clogged filters, algae or debris. Use this guide to help you determine which is the culprit in your cloudy pool.
Why is my pool water cloudy?
1. Are your chemicals properly balanced? (Check your chlorine, pH, alkalinity and calcium hardness.)
- Did you shock your pool recently? Is there is too much or too little chlorine?
- Is the pH and alkalinity out of balance?
- Does the water have high calcium hardness levels?
Solution: Too little chlorine is a leading cause of cloudy pool water. Chlorine is used to sanitize the water and without it, your water isn’t being properly cleaned. Contaminants in the water will build up and cause cloudy water as a result.
Make sure your pH, total alkalinity (TA) and calcium are all in the acceptable range and that the combination of the three aren’t on the high end of the range. If they are, your water is likely out of balance. If the temperature of your water is also on the high side, the imbalance of these chemicals is even more likely the cause of cloudiness. High pH, alkalinity and calcium hardness can lead to cloudiness.
If any of the above are out of the acceptable range, first thoroughly scrub, skim, and brush your pool walls, then vacuum. Once that is complete, work on adjusting the chemicals to get them within the acceptable range again. Re-balance your water by adjusting the pH. Use a pH reducer or increaser to adjust pH levels or add muriatic acid to lower TA. Be aware that even shocking a clean and balanced pool can cause cloudiness temporarily. Shock your pool water to remove harmful bacteria, organic contaminants, and algae. Finally, run your filter and test your water sample. Use a chlorine stabilizer (cyanuric acid) to protect your chlorine levels.
| Chemical | Industry Acceptable |
| pH (Potential Hydrogen) | 7.2-7.8 |
| TA (Total Alkalinity) | 80-120 ppm |
| Calcium | 200-400 ppm |
If your pool is 100% balanced and is still cloudy, you should also try a product like Omega Pool Clarifier, available in our store.
2. Is your pool filtration system operating properly?
Poor water circulation and filtration can occur when your filter doesn’t run long enough, becomes clogged or needs cleaning. Poor circulation can also be caused by skimmer and pump baskets becoming full of debris.
Solution: Turn over your pool water by running your pool filter continuously for at least 12 hours each day. A diatomaceous earth (DE) filter may achieve your desired results after only a few hours because it has the finest level of filtration. A cartridge filter will likely take 2-5 times as long, while sand filters can take multiple days. Add DE powder to your sand filter for more effective filtration. Is your filter clean? Have you back washed or cleaned it recently? If not, we recommend doing so. Most contaminants will be removed if your pool filter and sanitizer are working together. When the leaves are falling because it’s dry, we recommend emptying your baskets daily.
3. Are environmental factors to blame?
- Leaves, pollen and dust can build up in your filter and hinder the cleaning process. Other environmental factors from animal waste to rainwater runoff can cause your pool water to become cloudy and imbalanced. Runoff water brings nitrates, phosphates, and other chemicals into your pool throwing the balance out of whack. Algae can also pollute your pool water and can lead to cloudiness, using up your pool’s chlorine rapidly.
- Are swimmers clouding up your pool water? Sunscreen, hair products, bug spray, and other contaminants can contribute to your water clarity, or lack thereof.
- The sun alone can deplete your sanitizers. “Its powerful 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. This means less sanitizer and more dirt in your water.” – Swim University
Solution: See Solution #2 above. Hint: run your filter! Using an enzyme product such as Natural Chemistry Pool Perfect will also help with contaminants introduced to your water by swimmers. Maintaining proper levels of cyanuric acid, aka stabilizer or conditioner, will keep the sun from using up your chlorine.
The absolute best way to rid your pool of cloudy water is to prevent it from becoming cloudy in the first place. We recommend working with our team of professionals to create a pool maintenance schedule that you can implement or signing up for our Hassle Free Pool Care program. Contact us to learn more!
