Green pool water is often caused by the presence of algae in your pool. Algae blooms can appear when your pool has a low Free Chlorine. Exposure to high heat, heavy rain or poor circulation, without the use of a preventative algaecide, also increase your risk of developing pool algae. Stubborn pool algae can be hard to control if the appropriate steps aren’t taken to properly treat and prevent the problem. Follow these steps to treat and prevent green pool water.


Test and Balance Water

Always begin by testing your pool water. Your test results will tell you if your water parameters are unbalanced. Pay special attention to your Free Chlorine level. Low Free Chlorine can cause your pool water to turn green. Always maintain Free Chlorine between 1 -4 ppm. If needed, apply the appropriate chlorine and sanitizers to restore adequate sanitizer levels.  


Clean Pool Water and Surfaces

Skim water surface to remove visible debris, brush walls, vacuum and empty skimmer baskets. Concentrate on areas with visible dirt and little or no circulation. Cleaning your pool regularly is an effective step to prevent algae growth.


Apply a Shock Treatment

Crystal clear water starts by applying pool shock. Shocking your pool water helps to remove contaminants that may cause algae to grow and helps to improve water filtration.


Apply an Algaecide

Algaecides treat and prevent pool algae, but not all algaecides are created equal. To treat green pool water, ensure you select an algaecide that kills green pool algae. After treatment, some dead algae may remain in your pool. Continue to thoroughly brush your pool’s surfaces often.


Clean Filter

Backwash or chemically clean your filter, according to your owner’s manual, to remove organic and mineral build up. Allow your pump and filter to run continuously for 24 hours so that your pool’s entire gallonage has the chance to run through your clean filter.

For best results, test and balance your pool water weekly. Download the Clorox® Pool app for expert water analysis and product and dosage recommendations. If your green pool water persists, contact us to help further troubleshoot.