How to Get Rid of Black Algae in your Swimming Pool

Black algae is a type of bacteria that can be really tough to kill and control in your pool. Here we show you had to kill black algae fast and how to prevent it from coming back.

At a Glance







Add Swamp Treat™

Add one (1) bottle of Swamp Treat™ per 20,000 gallons of pool water. 



Brush the walls of the pool. You’ll need to get as much of the black algae off the surface as possible, so some scrubbing might be needed. 



Add approximately 2 pounds/gallons of shock per 10,000 gallons – cascading it around the pool.



Set your system back to filter, and turn the pump on. Allow to filter for 24 hours

What You’ll Need

  • Swamp Treat™ Rescue Algicide
  • Pool Shock of your choice (See tips)
  • Brush Attachment (See tips)

Extra Tips

  • For plaster, you’ll want to use a 50% stainless steel brush (sometimes referred to as an “Algae Brush”) to get as much black algae in the pours of the plaster.
  • For best results, we recommend using Trichlor-s-triazinetrione (usually referred to as “trichlor”) granules for shocking. For color/painted/vinyl surfaces don’t allow the granules to sit on the surface or it could lead to bleaching.
  • Keep your filter running continuously to help get rid of the dead algae.
  • Backwash your filter when the filter pressure rises above 10 psi than normal.
  • Consider using a preventative algicide such as No Mor Problems® with your sanitizer to keep black algae from returning.

Still need help?

Still have questions? Need an expert’s advice? Visit our support center for additional documentation and to open a ticket with a Pool Technician.

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