Pool Mustard Algae

Mustard algae is a chlorine-resistant yellow algae that clings to pool surfaces and is often mistaken for pollen or dirt.

How to Identify Mustard Algae

Unlike green algae, mustard algae does not float freely in water but attaches itself to walls, steps, and ladders. It is more common in warm, sunny climates.

How to Remove Mustard Algae

  • Brush the affected areas to loosen algae.
  • Use a mustard algae-specific algaecide.
  • Shock the pool and maintain high chlorine levels.
  • Wash pool toys, swimsuits, and cleaning equipment to prevent reinfection.

Related Terms

  • Algaecide – A treatment designed to kill and prevent algae growth.
  • Shock Treatment – The process of adding a high dose of chlorine or oxidizer to break down contaminants.
  • Free Chlorine (FC) – The active and available chlorine that sanitizes pool water.

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