"Coralife Super Skimmer Needle Wheel Protein SkimmersThe Super Skimmer is a high performance foam fractionator designed with a patented needle-wheel impeller, combined with an aspirating venturi. This mixture allows the needle wheel to divide the fine bubbles into a dense froth which is injected into the reaction chamber. The deposited air bubbles and water mix together in a spiraling vortex inside the reaction chamber to increase both contact time and efficiency. As the bubbles rise, their surface areas attract and collect fine proteins and organic compounds before they break down in the water and are then deposited into the collection cup. The efficient removal of highly concentrated waste products results in a better environment for the aquarium. Easy-twist removable collection cup with drain line for easy cleaning. Equipped with versatile water level adjustment dial to easily stabilize water flow within the reaction chamber. Dual 45° injection outlets increase contact time in the reaction chamber for maximum skimming efficiency. Protein skimmer has a 500 gph flow rate.For Hang-on Tank Mount:Hang-on tank mounting bracket for up to 1.125"" size tank mouldingsMinimum 8"" clearance between the aquarium and the wallFor Sump Hook-up:Miniumum 0.5"" clearance between top of the stand and the skimmer.."