What can cause cloudy water in a swimming pool?

Cloudy water in a swimming pool can be attributed to a variety of factors, making "all of the above" the most comprehensive and accurate choice.

A filter malfunction can impede the pool’s ability to effectively remove contaminants and debris from the water, leading to cloudiness. This can happen if the filter is dirty or if there are issues with the pump.

An excessive bather load introduces more organic material, such as sweat, oils, and dirt into the water. This increase in contaminants can overwhelm the sanitation system, resulting in cloudy water.

Chemical imbalance, particularly issues with pH levels, sanitizer levels, and alkalinity, can also contribute to cloudy water. When these parameters are not within the ideal range, it can hinder the effectiveness of disinfectants and lead to poor water clarity.

Since each of these factors can independently result in cloudy water, and they can also interact with one another to exacerbate the problem, the answer comprehensively covers the main causes of cloudy pool water.