There are several reasons why pool water might be cloudy, but if your pool water is clean and well filtered, then chances are that the cloudiness may be a PH issue. Pool water should be maintained at a PH level of between 7.2 and 7.8, but the ideal range is between 7.4 and 7.6. If the PH is over 7.6, you are likely to experience cloudy water related to PH levels. Remedying this problem is simple and quick.
Test your pool water with the acid demand kit to determine your water's PH level. Acid demand kits are available at pool supply stores.
Follow the link listed in the resource section of this article to find a table that will help you to determine the correct amount of acid to add for your particular pool's water capacity. This link will also aid you with all sorts of chemical balance questions as they relate to swimming pool water.
Carefully add the required amount of acid to the deep end of your pool. Avoid pouring acid near pool walls, fittings, ladders, or any other type of hardware. Pour slowly to prevent splashing this corrosive substance on any skin, decking, clothing, or other objects.
Allow the pool water to circulate for several hours and retest the water with the acid test kit to be sure your water is within the correct range.