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How to Remove Black Algae Spots from Pool

By Clark Rubber | 5th January, 2021
How to Remove Black Algae Spots from Pool

Black spot algae is an unsightly blemish in your pool interior and can quickly spread to cover the entire interior surface of your pool.

What you’ll need:

Eliminate Black Spot algae by following these simple steps:

  • Have your water professionally tested at your local Clark Rubber store before commencing any chemical treatments.
  • Adjust pH between 7.0 and 7.2. At a lower pH the waxy coating surrounding algae cells is greatly softened and allows better penetration.
  • For concrete and fully tiled pools, use a stainless steel brush to scrub the surface of the black spot algae. 
  • For fibreglass and vinyl lined pools, use a nylon brush to scrub the surface of the black spot algae. 

      NOTE: This process is not designed to brush the stain away, but rather to break the ‘surface’ of the algae to allow the algaecide to penetrate into the black spot. 

      Do not scrub vinyl lined or fibreglass pools with a stainless steel broom.

  • Use Filtrite Blackspot Algaecide. Place product directly onto black spots. Wait 24-36 hours. Scrub with brush if necessary.
  • Add Filtrite Extreme Algaecide at the rate of 2.5 litres per 50,000 litres.
  • Run filter 8 hours per day. Ensure water flow is being distributed over infected area by adjusting the pool return outlets. Check the pressure gauge on the filter regularly and clean the filter when necessary.
  • Brush black spot daily for a week.
  • It may take up to 2 weeks for algae to die.
  • Re-adjust pH level between 7.4-7.6.
  • Regularly treat pool with Filtrite Algygone every 3 months. Use Filtrite Phosphate Eliminator to reduce nutrient level. If persists, visit your local store. Add Crystal Clear Clarifier Pill to Skimmer Box to improve water clarity.

Always follow the manufacturers directions provided on the product.