Large ponds and aquariums need a powerful pump. O.S.I.'s Submersible Pond Pumps are a reliable choice for a fountain, waterfall or filter. These durable, efficient pumps are constructed of non-corrosive materials with ceramic shafts for long life. The body is epoxy sealed to protect electrical components making each unit completely submersible. The GP-4000 Water Pump is strong enough to handle applications of up to 5000 gallons with a reliable flow of 2160 gallons per hour. This versatile pump can be used as a submersible pump or plumbed inline with your system. This pump will accommodate 7/8 - 1 1/4 in. diameter tubing.