The Coralife Turbo-Twist 12X 36 Watt UV Sterilizer is for tanks up to 300 gallons.36 watt compact fluorescent UV lampMinimum flow: 300 gph. Maximum flow: 900 gph.In line or hang-onConnections: 1" or 5/8" ID Hose. You'll need at least four feet of clear hose.Requires pump--we recommend the Rio 1100Dimensions: 21" X 6"User Manual (pdf file in new window)