Black Pool Stains: Causes + Fixes
Black algae or manganese.
What Causes It
Black algae or manganese.
How to Fix It
Brush hard with wire brush, triple-shock, add algaecide.
When to Call WETYR
If DIY does not resolve the issue within 48 hours, schedule a WETYR service visit. Typical diagnostic + first hour: $185 to $285.