The Aquatop CF500-UV canister filter holds more media than a standard internal power filter; making it ideal for larger or heavily stocked aquariums. The filter also includes a built-in 9w UV sterilizer that helps kill bacterial and the uni-cellular algae that causes green water; leaving your water clean and crystal clear. Easy to set up and maintain; the filter includes a self priming pump and all of the necessary tubing and plumbing parts. The filter also comes with a single disconnect valve to shut off the inlet and outlet tubes; making cleaning simple and free of spills. Designed for super quiet operation on fresh or salt water aquariums. The CF500-UV allows you to use your preferred media to fully customize the filtration of your aquarium. The filter comes with four trays; each of which can be used for mechanical; chemical and biological filtration. Fine and Coarse replacement mechanical filter pads are available to help remove fish waste and debris. Carbon can be used for chemical filtration by removing dissolved organics; odors and discoloration. Biological filtration can be added with ceramic rings; which provide surface area for the growth of beneficial biological bacteria. The CF500-UV is rated at 525 gph and is good for aquariums up to 175 gallons. The canister measures 11.4 in. x 11.4 in. x 19 in. and weights 13.2 lb.