Spa water is foamy and leaves residue on the surface when jets are running.

Safety: Avoid adding household detergents or non-spa chemicals to the water.

• Step 1 – Skim and clean: Use a skimmer net to remove foam and surface debris. Wipe the waterline with a spa-safe cleaner.
• Step 2 – Test and balance: Check pH, alkalinity, and calcium hardness. Adjust to Catalina's recommended ranges; low calcium can increase foaming.
• Step 3 – Clean or replace filters: Rinse filters thoroughly. If they are saturated with oils, soak in a filter cleaner and rinse, or replace.
• Step 4 – Partial drain: If foaming persists, drain 50–100% of the water and refill with fresh water.