Cloudy pool water is uninviting compared to sparkling, clear pool water. The cause of cloudy pool water is often a pH level that is too high. The pH level indicates the acidity of the water, which affects every chemical balance in the pool. The ideal pH level for pool water is between 7.4 and 7.6. Often the continued use of chlorine, which is mostly alkaline, combined with bodily fluids, raises the pH to above 7.6, causing cloudiness. To counteract the raised pH level and clear the water, add muriatic acid to reduce the overall alkalinity.
Put on protective clothing, protective goggles and gloves.
Use an acid-demand test kit to determine the current pH level of the water in the morning.
Follow the manufacturer's instructions on the muriatic acid to determine how much acid to add to the water. The amount is based on the number of gallons of pool water and the current pH level.
Fill a plastic bucket 3/4-full with pool water. Add the acid to the bucket.
Run the pool pump. Slowly pour the mixture into the deep end of the pool while walking around it. Do not add large amounts of acid to the pool at one time and avoid pouring it on pool walls and fittings.
Allow the pump to circulate the water for at least four hours. Retest the pH level. If needed, add more muriatic acid until you reach a pH reading between 7.0 and 7.6.