Spa water has a strong musty or moldy odor, even after adding sanitizer.

Safety first: Avoid using the spa until water quality is restored.

• Shock the spa: Add a high dose of chlorine or non-chlorine shock according to Artisan Spas water care guidelines.
• Clean or replace filter: Remove the filter and soak it in a filter cleaner solution, then rinse thoroughly or replace if old.
• Clean cover: Wipe down the underside of the spa cover with a mild bleach solution (if compatible) and rinse well.
• Drain and refill: For persistent odors, drain the spa, use a line flush product to clean plumbing, then refill with fresh water and balance chemicals.