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

Safety first: Avoid adding excessive chemicals at once; test water first.

• Use foam reducer: Add a small amount of spa-approved defoamer to temporarily reduce foam.
• Balance water: Test and adjust calcium hardness to manufacturer recommendations to reduce foaming.
• Drain and refill: If water is old or heavily contaminated, drain the spa, clean the shell, and refill with fresh water.