Unpleasant musty or moldy smell from spa or cover

Safety first: Do not use the spa until sanitizer levels are corrected and odors are resolved.

• Shock the water: Add a strong shock dose and run the pump continuously for several hours.
• Clean cover: Remove the cover and clean both sides with a mild disinfectant safe for vinyl. Allow to dry completely before replacing.
• Replace filter: Install a new filter cartridge if the old one is slimy or has a persistent odor.
• Vent regularly: Periodically open the cover to allow moisture to escape and run the pump to circulate water.

Severe or recurring odors may require a full drain, shell cleaning, and line flush with a spa system cleaner.