Most Common Causes of Cloudy Swimming Pool Water

Your goal as a swimming pool owner is to maintain crystal clear pool water all year long. But it’s inevitable that some day, probably to your surprise, the water will start turning cloudy. Now it’s up to you to figure out why. Following are the most common reasons why a clear pool one day can suddenly and unexpectedly turn into a cloudy pool the next.

Swimming pool water clarity is dependent on three basic elements of pool maintenance… filtration, circulation, and water chemistry. If one or more of these three elements are out of whack, the pool could turn cloudy.

Filtration – there’s no doubt that without sufficient filtration, the pool water will soon turn cloudy. Possible reasons for inadequate filtration are a dirty filter, an old filter element that needs replacement, and not running the filter long enough each day. Insufficient filtration can also be caused by a lack of circulation… see below.

Circulation – turn on the pool pump and confirm that the pool has good circulation. All it takes is a clogged skimmer or pump basket to restrict water flow resulting in inefficient filtration. If all the baskets are clean and there still isn’t good circulation, the pump impeller may be clogged with debris and will need to be cleaned out. Lastly, check all circulation diverter valves to make sure they are in the correct position. If a valve has been inadvertently turned to block either an intake line or a return line, circulation will be disrupted.

Water Chemistry – keeping the pool water chemistry balanced is a key to clear water. The most common mistake is letting the chlorine level drop to zero. This will cause cloudy pool water, which is a sign of early algae growth. Next check the pH, alkalinity, and calcium hardness. If any of these parameters are outside the normal range, this could be the problem also.

Most cloudy pool water problems are solved by simply checking these three areas of pool maintenance, and much of the time it ends up being real obvious. If you are not able to identify the problem, it is time to seek out a professional for help. Call the local pool store or a pool service technician to help troubleshoot and fix the problem.