This Active Aqua water pump comes in a 4 pack of pumps. The 550 GPH Active Aqua Submersible Pump was built to go below the waterline in your pond. Active Aqua's entire collection of pumps complete any grow setup, but for hydroponic systems, you can't beat the submersible line. All of Active Aqua's submersible pumps include multiple hose fittings so you get an exact fit every time. Each pump's powerful mag drive construction includes removable foam filters, impellers, rubber mounting feet to reduce vibration, and a 6-foot heavy-duty power cord. The Active Aqua Submersible Pump moves 550 gallons per hour and is recommended for 55 plus gallon reservoirs, but you can adjust the pump's flow to move at your preferred rate. And as an added bonus, with its dependable design, feel free to use this pump inside or outside.