The Rainbow Models 300 and 320 automatic chlorine/bromine feeders not only save time, but also reduce manual handling of chemicals. They use large or small Trichlor or Bromine slow-dissolving tablets to make sanitizing your new or existing pool or spa easy and automatic. Both install easily on the pressure side of the pump, downstream of the filter and heater. The freestanding Model 300 and the in-line Model 320 both feature an external fine control valve that l