Coralife Turbo-Twist 3X 9 Watt UV Sterilizer is for aquariums up to 125 gallons.9 watt compact fluorescent UV lampMinimum flow: 100 gph. Maximum flow: 200 gph.In line or hang-onConnections: 1/2" or 5/8" ID Hose. You'll need at least four feet of clear hose.Requires pump--we recommend the Rio 400Dimensions: 11" X 2-7/8"User Manual (pdf file in new window)