The Rapids Pro PS3 Aquarium Filtration System supplies optimum and efficient mechanical, chemical and biological filtration for saltwater fish only aquariums up to 100 gallons. This filter system siphons the dirtiest surface water out of the tank using the Rapids Surface Skimmer Overflow and the Aqua Lifter Air Pump with hanger. Water then is filtered in the Large Capacity Filter, which contains an air driven protein skimmer as well as carbon and biological media. Water is returned by the 1,000 gph pump through the Rapids Surface Skimmer Overflow back into the tank through a multi-directional return nozzle. The Rapids Pro provides absolutely all the filtration and water movement you could possibly need in a saltwater fish only aquarium of 100 gallons or less.Includes:Large Capacity Filter (pictured). Includes baskets with mechanical filter pads (top basket), activated carbon (middle basket), sintered glass bio-media (bottom basket). The water pump and the protein skimmer are integrated into the filter. 16" X 9" X 23" Tall. an additional 3.5" is needed for skimmer cup removal.Protein Skimmer (pictured, integrated into the Large Capacity Filter). A specially designed air driven counter-current skimmer for removing organics before they break down into ammonia and nitrite compounds. Collection cup comes with a drain outlet. With airline hose the waste can be drained into an empty gallon container.1,000 gph pump. Integrated into the Large Capacity Filter.Stellar Plus Air PumpAqua Lifter Air Pump with hangerRapids Surface Skimmer Overflow. For siphoning water out of the back of the tank and back into the tank. 8" Long X 6.5" Wide X 7" Tall. To fit the suction/return into your tank you will need an aquarium top opening of 7.5" X 2".