Designed to fit conveniently inside of your spas filter cartridge, this is the only hot tub mineral sanitizer designed with the patented FROG mineral protection for hot tubs up to 600 gallons. Reduce the usage of chlorine and bromine by up to 50%, stop faded swimsuits and powerful odors with FILTER FROG. FILTER FROG lasts up to 4 months and it features an easy reminder dial to help you remember when to replace it.

Use the Spa Frog Mineral Cartridge refill in either the Spa Frog Floating System, or for users of the Spa Frog Inline System which is factory-installed in some hot tubs. The minerals typically last approximately 4 months. Use with Frog Bromine Cartridge.