07/19/2025
YELLOW ALGEA ANYONE???
Yellow algae—also called mustard algae—is a type of algae that grows in swimming pools and is yellow-green to mustard brown in color. It’s different from the more common green algae in a few key ways:
🔍 What is Yellow Algae?
Scientific name: Xanthophyceae (a group of algae)
Appearance: Dusty, powdery, or slimy yellow/mustard-colored patches, often in shady areas of the pool (like corners, steps, or behind ladders).
Texture: Often brushes off easily but comes back quickly if not treated thoroughly.
Resistance: Very chlorine-resistant. It forms a protective layer (biofilm) that makes it harder to kill than green algae.
🧪 Why It’s a Problem
It clings to surfaces and hides in pool equipment, plumbing, and cracks.
It can survive even after brushing and normal chlorination.
Left untreated, it can spread and make the pool unsafe and uninviting.
✅ How to Treat Yellow Algae
Here’s what typically works (and what you might do as the pool service pro):
Brush it thoroughly – especially in shaded and low-circulation areas.
Superchlorinate/Shock – Use a high dose of chlorine shock, ideally a calcium hypochlorite-based one.
Add an algaecide – A mustard or yellow-specific algaecide works better than general ones.
Run the filter continuously for at least 24 hours.
Clean all accessories – Floats, brushes, poles, and even bathing suits can hold spores. Encourage the customer to wash these.
Vacuum and backwash after treatment.
💡 Pro Tip for Your Customer
Let your customer know: "This type of algae is stubborn and can come back if not treated aggressively the first time. But with the right combo of brushing, shock, and algaecide, we can knock it out and keep your pool crystal clear."
If you want, I can also write a note or message you can send directly to your customer about what you're doing to treat it.
Westco Collect
Westco Designs
ProPools
Call now to connect with business.