These well designed out of pond gravity designed filtration units are small on size yet big on performance. Powerful 3 stage Mechanical & Biological Filtration assures optimal water quality and healthier fish. Large easy-to-open top makes maintenance a snap while the green coloration helps blend filter into the natural surroundings. The revolutionary design of these filters combines Ultraviolet clarification, mechanical filtration and biological filtration to guarantee clear purified water. All models feature U.V. bulbs positioned above the water to eliminate the need for quartz tube replacement or problems associated with frost damage or scaling. Periodic filter foam rinsing and annual bulb & foam replacement is the only maintenance required. For up to 1200 gallon ponds. Max Flow Rate: 500 GPH, Power Cord: 12’, Inlet: ¾” or 1” Barbed, Outlet: Single or Dual 1-1/2”, Dimensions: 14”L x 11”W x 7.5”H.