How to diagnose and cure cloudy pool water
One of the biggest problems associated with swimming pool maintenance is cloudy water. Cloudy water is the result of either, very fine particles of debris being suspended in the water, or a chemical imbalance.
The two most likely causes of cloudy (or misty) looking water are the pH and calcium hardness. This requires that the water be tested for combined chlorine, alkalinity and calcium hardness, and pH.
The ranges within which these test results should fall are as follows.
- pH = 7.2 - 7.6
Free chlorine = 1 - 3 ppm
Calcium hardness = 200 – 350 ppm
Alkalinity = 90 – 120 ppm
If any of the levels fall outside these ranges it will be necessary to make adjustments to the chemical levels, following which the pool pump and filter system will need to be left running for approximately 24 hours. After this time further testing can take place.
Once the levels have been correctly balanced the water should return to a crystal clear clarity. If it does not, then the cloudiness is most probably the result of fine floating debris and the problems most likely cause is the filtration system. The solution is to backwash or clean the filter (the method will be determined by the type of filter, i.e. D.E., Sand or cartridge) and then to run the pump and filter continuously for between one and two days.
If cloudy water still persists and there in no problem with either the chemical levels or the filtration system it may be necessary to use swimming pool clarifying chemicals.
These chemicals should initially be added in small doses whilst continuing to run the filtration system for 12 to 24 hours between each treatment. Once the water is clear the treatment can be stopped. These clarifying chemicals help remove tiny particles of debris that are suspended in the pool’s water.
If all of the methods above fail to work it may be that the condition of the pool water is too severe for a clarifier. The final and last resort is to use a floc which will have the effect of causing all of the suspended particles to the pool’s floor where they can be removed by vacuum suction.
If a pool is monitored and treated on a regular basis cloudy water should not be an issue. However short term cloudiness can result for a short period after chemicals have been added, which is why all treatments generally require between 12 and 48 hours to take full effect. Failing to wait for an appropriate period may result in a pool being over treated with chemicals.