Reef Octopus BH90 Hang on Protein Skimmer Item #: BH90HOB Height: 23.8" Footprint: 7.5" x 7.5" Reaction Chamber: 4" Pump: OTP‐1000s Fit tanks up to: 75～100Gal BH‐90 skimmer is totally a new hang on skimmer, not like your common hang on design, it have a cylindrically main body and use the siphon to feed water in to the skimmer which reduces the load on the pump while increasing the air generated. This skimmer skims the top of the water surface avoiding the ugly oil buildup on the water surface. A cylindrical reaction chamber, the bubble chamber and conical body to neck transition，all help disperse the air gently and reducing turbulence as the collected organics make it into the collection cup. It is also very easy to be set up. Two adjustable PVC screws makes it could be stably fixed on your aquarium tanks.