How To Clean Cloudy Pool

Get your pool water clear and sparkling

If your pool water is cloudy, there are several things that could be wrong. It is important to look for the cause before treating cloudy water. If you don’t find the cause, the pool will go cloudy again in a few days and you will have wasted your time.

Check your filtration and circulation system

Is the filter working properly? If the flow isn’t strong enough to push your hand away, you may be having problems with your filter and service may be required.

  • Does the filter need to be backwashed?
  • Are there any blockages or a build-up of debris?
  • Has the filter been chemically cleaned recently?
  • Is there enough sand or DE (Diatomaceous Earth) in the filter?

Ensure your filter is running for up to 12 hours a day depending on the season.

Check the chlorine level

The free chlorine level in the pool should be maintained between 1.0 and 3.0ppm. There are products available that assist your sanitiser by preventing bacteria and algae while removing organic waste build-up, which will help maintain the free chlorine level and reduce incidences of cloudy water. Check if chloramines are present, that is can you smell a very strong chlorine smell?

Check the pH and Total Alkalinity (TA)

The pH needs to be within the range of 7.2 and 7.6 and the TA between 80 and 120ppm. If the water is out of these ranges, it can cause cloudiness and build-up of scale. Your local SPASA pool shop can test all of these elements and make recommendations on how to keep these in balance.

Check for algae

Algae infestation, even in its early stages, can cause cloudy water. Ensure you add a preventative dose of algaecide every week. Algae may not always be visible, you may notice it because stairs, walls or fixtures are sticky or slimy. If the pool is cloudy because of an algae infestation, you will need to undertake a full algae treatment<Link to green pools page>.

Treatments for cloudy pools

After ruling out the above causes, the following treatments can be administered.

Cloudy water can also be a sign that superchlorination is needed

If there is an excessive presence of chloramines, the pool will have a strong smell of chlorine and the water will make eyes sore and/or skin itchy when you get out of the pool. These are all signs that the water may need to be superchlorinated. Another sign is when pool water is hazy after a days’ swimming – caused by a buildup of skin proteins, or high bather load.

  • Add a three times daily dose of Chlorine. Liquid is easiest, 5 litres in a 50,000 litre pool, but use granular if Liquid is not available (360 grams of Calcium Hypochlorite)
  • Adjust pH to 7.2 with acid; the extra Chlorine added will raise the pH, especially Liquid.
  • Leave the salt chlorinator running as normal 
  • Swimming needs to be stopped for 2 hours after adding any chemicals

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