My pool water is green: what should I do?

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Has your pool water turned green?
Don’t panic!
There are solutions to turn your green water fairly quickly into clear, hygienic water.
To do so, you need to use the appropriate products and administer them using the correct method.

Stérilor offers advice to remedy green water in your pool.


Green pool water: what are the causes?

If your pool water turns green, it may be due to a number of causes.
The most common are a rise in temperature, a poorly-maintained and insufficiently-cleaned filter, or too short a filtration time.
A chlorine overdose may also be the reason that a water becomes green.
In fact, excess chlorine harms its efficiency, thereby allowing bacteria and algae to develop in the pool.
Similarly, a disruption to the pH level of your pool water might also be a cause.


How to return it to a clear, clean water?

To resolve a case of green water, no need to empty your pool.
Simply follow the steps here:

      1. Analyse the pH of your water

        Before doing anything else, it is important to test the pH of your pool water.
        It is often due to a pH imbalance that the pool water becomes green.
        A pH too high (above 7.6) inhibits the level of free chlorine, which is not sufficient to disinfect the water.
        Algae will proliferate and the pool water will become green. As a reminder, the pH level must lie between 7.2 and 7.6.
        If this is not the case, adjust it before commencing any other treatment.
      2. Apply a shock treatment to green pool water

        Once the preceding step is complete, you need to apply a shock treatment.
        Ensure that it is perfectly suited to the disinfectant used in your pool.
        Note that for effective cleaning, you will need to leave the filtration system in operation continuously.
        We recommend that you ask your dealer for advice on the correct dosage and the appropriate products. Then clean the walls and bottom of the pool.
        Once complete, wash and rinse your sand filter.
      3. Add an algaecide and a flocculant

        To efficiently combat algae and ensure high-quality water, you can add an algaecide and a flocculant.
        The algaecide will eliminate the algae while the flocculant will improve the performance of the filter, which will optimise water cleaning as well as the effectiveness of the treatment and disinfection products.


      How to prevent my pool water from turning green?

      To prevent your pool water from turning green, you need to ensure that the pH and chlorine levels of your water are correctly balanced.
      This is a primordial parameter to ensure hygienic, crystal clear water.

      In parallel, it is recommended to regularly monitor and clean your filtration system as well as all pool equipment such as skimmers, pool walls, filters, etc.

      To complement the action of chlorine, you can use an anti-algae as a preventive treatment.

      Lastly, make sure you remove the pool cover in periods of hot weather.

      Eradicating green water is possible, but it will require plenty of attention.
      This is why we advise you to regularly monitor your pool water, and especially its pH level.

      To avoid the unpleasantness of green water, you can also use automated water treatment systems such as salt electrolysis.