How to get rid of Mustard Algae in Swimming Pools

From Florida to California and everthing in between; Mustard Algae is the most common form of swimming pool algae. Odds are if you've owned a swimming pool, you've ran into this yellowish sandy looking algae growing in the shady areas of your pool. Here we give you step by step directions on how to get rid of mustard algae.

At a Glance







Add Yellow Treat®

Add one bag or one capful (5 oz.) of Yellow Treat® per 10,000 gallons of water in the areas with the most mustard algae



Brush the surface of the pool, concentrating on areas with the most mustard algae. One good push of the brush over an area should do the trick.



Shock the pool with your choice of chlorine – using about 2 pounds/gallons of chlorine per 10,000 gallons of pool water. Refer to the directions on your chlorine for “super-chlorination” specific dosing.



Let the filter clean up the dead mustard algae, and backwash the filter when the pressure gets high. Refer to the filter manual for back-washing recommendations.

What You’ll Need

  • Yellow Treat®² Rescue Algicide
  • Pool Shock of your choice
  • Brush attachment

Extra Tips

  • Keep your filter running continuously to help get rid of the dead mustard algae.
  • Back wash your filter when the filter pressure rises above 10 psi than normal.
  • Don’t pour shock directly on colored surfaces. This can discolor your surface.

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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