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White Algae in My Pool

By Cleveland Van Cecil
Algae in a swimming pool is often caused by an imbalance of chemicals.
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Algae often occurs in pools that are not cleaned properly and whose chlorine balance has dropped. Maintaining free chlorine levels between 1 and 3 parts per million (ppm) will prevent the growth of algae. Usually green algae appears, but white algae sometimes does, followed by a pink algae that grows on top. Although these are often called algae, they are in fact fungi (Paecilomyces lilacinus) forming on the water. They are treated in the same way as most algaes.

Skim algae off the surface of the pool as much as possible, using a pool skimmer. Rinse the end of the skimmer with bleach to kill the fungi that attach to it.

Vacuum the pool with your pool vacuum. Vacuum then brush the sides of your pool with the pool brush. Vacuum again. Rinse everything in bleach to kill the fungi.

Place a rubber glove over your hand and take a water sample from elbow depth. Pour the water into your water testing kit and add the chlorine sampling solution. Compare the color of the water to the color chart to determine the chlorine level.

Compare the chlorine level to the side of your pool shock bag and measure out the amount of pool shock needed for your pool. Pour it into a bucket of water and add to the pool according to package directions. Cycle the pool filter for 24 hours.

Test the chlorine levels again. The water is safe to swim in once chlorine levels reach 1 to 3 ppm. You may need to clean the water several times before the fungus goes away.


Things You Will Need

  • Skimmer
  • Bleach
  • Pool vacuum
  • Brush
  • Pool testing kit
  • Pool shock