Top Grade Fish Sea Grass Plant Weed Tank Aquarium Pond Protein Skimmer Fish Tank Filter Pump 300 GPH Aquarium protein skimmers are one of the most important devices you can use to maintain water quality in an aquarium. A protein skimmer is a chamber with a column of bubbles. Surface tension attracts organic waste to the bubbles & carries it through the column; then it's "skimmed" into a collection cup. With our heavy duty skimmer, the gas exchange can be accelerated and improved more efficiently so that the water and the micro air bubbles in the vortex chamber biologically react to naturally filter your aquarium. Really an inexpensive way to improve water movement especially for saltwater coral, reef or fish tanks!!! This is exactly what you need to get your aquarium activated and improved !!! Don't hesitate! No more dead spots or dormant living space from now on!!!