Reef Octopus Classic 100-HOB Protein SkimmerHang On Back Skimmer for aquariumsup to 105 Gallons Footprint: 8" x 3. 75" Height: 17" Pump: Reef Octopus Aquatrance 1000s Simple to Operate Hang On Back Skimmer The Classic 100 HOB is a proverbial favorite amongst hang on back skimmer users capable of filtering aquariums up to 105 gallons. The Classic 100 HOB features an easy to install and operate design in which the pump is mounted inside the aquarium. To install, simply place the skimmer on the