The AQUATICLIFE RO Buddie +DI is a four-stage RO/DI unit designed for residential use to remove the Total Dissolved Solids (TDS) from tap water. Each RO Buddie includes a Sediment, Carbon, Membrane and DI Resin cartridge. Useful applications include smaller aquariums, fountains, humidifiers and more. With incoming water pressure at 65 PSI and water temperature at 77°F, the RO Buddie +DI will produce up to 50 gallons in a 24-hour period, or a little over two gallons per hour. The included tubing and fittings make setup quick and easy.