The most common reason for a cloudy pool is no chlorine. Contaminants such as sweat, urine, dead skin, lotions, oils and other waste bathers leave behind, build up rapidly and drastically deplete sanitizer levels. High winds, heavy rain, thunder storms or other extreme weather can bring dirt, debris and other small particles into your pool also causing the premature consumption of sanitizer levels. Once your sanitizer levels drop too low, your pool water will start to look hazy. This is usually when algae growth begins and it can take over your pool very quickly. Making sure you are on a comprehensive weekly maintenance program, can help ensure this will never be an issue in your pool.
Another very common cause for cloudy pools is unbalanced water. Certain chemical levels to keep an eye on include your PH levels, Alkalinity levels and Calcium levels. For example, if these levels are too high, the water has a difficult time holding mineral particles in suspension, causing the water to look cloudy. This can also lead to scale build up on the surface of the pool.
Although water chemistry plays a major role in how clear your water looks, two other important factors to consider are circulation and filtration. If a pool has inadequate circulation or filtration, it does not matter how many chemicals you add to the water. Ensuring that chemicals are being dispersed properly through the pool as well as filtering out bather and environmental waste, play a pivotal role in keeping your pool water crystal clear.
If your pool has inadequate water circulation, it can cause debris and other particles to settle at the bottom of the pool and any chemicals that are added will not be distributed evenly through the water. Running your pump continuously will make sure there is never any standing water and will reduce the amount of fine debris that can settle on the pool floor. Positioning your return jets on a 45 degree angle downwards and turned slightly to the right, will make sure you are not just circulating surface water and are efficiently moving dirty water to the skimmer.
The filtration system should also be properly maintained so that waste, bacteria and microorganisms can be filtered out of the water. Backwashing sand filters and rinsing cartridge filters when needed will help remove trapped dirt and debris. You should also chemically clean the filter media at the end of every pool season to remove greases, oils and anything else that cannot be removed through backwashing or rinsing cartridges. If your filter media is over 5 years old, you should consider changing the sand or replacing the cartridge elements.