King Technology Frog Mineral System - The Frog Cycler - In-ground Pools 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! Fresh Mineral Water System for Pools 10,000 to 40,000 gallons Pre-filled cartridges for no mess, no guess and no stress pool care. Kills bacteria with up to 50% less chlorine* Mineral Reservoir lasts all summer or 6 months whichever is shorter Application: For inground pools, only