Reef Octopus® BH2000 HOB skimmer with external OTP 2000 pump Dimensions: 10" x 4" x 21" Rated up to 140 gallons Powered by 1 OTP 2000 pump at 500 gph Wattage: 21w Air Draw: 420 L/H (15SCFH) High performance venturi air injection system 1 year warranty on skimmer and pump The BH2000 is a unique design HOB skimmer in that the pump is mounted external and under the actual skimmer body. By placing the pump outside the skimmer and the aquarium there is no heat exchanged to the water. This design also allows for easy removal of the pump for cleaning and maintenance. This Reef Octopus skimmer is powered by the Hailea OTP 2000 pump and built with high quality acrylic. The Octopus skimmers uses metric plumbing parts. The pump has an improved venturi design and pinwheel impeller.