Pool Frog 01-01-5480 Series 5400 Inground Swimming Pool Mineral Sanitizer Cycler New Pool Frog 01015480 In Line Chemical Feeder for Inground Swimming Pools/Spas -Mineral Reservoir included (Up to 40,000 gallons) Reduces chlorine use by up to 50% Patented mineral technology keeps your pH balanced by acting as a neutralizer The POOL FROG Cycler acts as the "water treatment center" and controls the flow of water through the system. No extra plumbing. No electricity. No extra headaches! Easy to install