In our Rainbow Collection we have the Rainbow Lifeguard Commercial 329x free standing Erosion feeder, Rainbow Lifeguard 300 offline Erosion feeder, Rainbow Lifeguard 320 inline Erosion Feeder and Rainbow Lifeguard Spa Chlorine/Bromine Floating Dispenser. Rainbow's offline chlorinators are designed for large pools or pools with high chlorine demands. They work on the pressure side of the pump and is used with a slow dissolving Trichlor tabs and sticks. They hold approximately 3 times more than the 300 and will dispense 5 times the chlorine or bromine. Includes a heavy-duty 1/2 in. control valve and a replaceable 1/2 in. check valve. The Floating Dispenser is designed to handle spas and small above ground pools. Its filled with foam for added buoyancy. The Chemical dispensing is controlled by adjusting the amount of chemical exposed to water by a unique dial adjustment.