Cloudy pool water is a common occurrence in pools. This is caused by suspended particles that cannot be easily filtered out. There can be quite a few reasons why your pool water is cloudy. Some of the most common reasons include:
Chemical balance of water is off. If pH or chlorine levels are off then that could be a reason for cloudy water.
If the pH levels are too high it inhibits the action of chlorine. This results in low chlorine levels that promote algae growth which then causes cloudy water. Algae growth causes cloudy or green water.