Spa Filter Clean is specially formulated to eliminate suntan oil, grease, as well as scale and mineral deposits from spa filters of all types. First clean filter with a garden hose and then allow it to soak in a solution of "Filter Clean" and water for 12 hours, remove and allow to air dry before replacing filter cartridge back into spa. We obviously recommend a spare filter to use while one is being cleaned. Properly cleaning and rotating of two filters extends the life of both filters saving you money over time.