Formerly known as the Spa Frog Mineral Cartridge, the Spa Frog Conditioning Cartridge refill is for use in either the Spa Frog Floating System, or for users of the Spa Frog Inline System which is factory-installed in some spas. Use with companion Frog Bromine Cartridge Replace the conditioning cartridge every 4 months when draining and refilling the spa. .
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