Best Choice Products 4000L Pressure Bio Filter for Pond w/ 13W UV Sterilizer Purifier Light, Flow Indicator - Black/Blue STRONG FILTER: Powerful enough to filter up to 2500 gallons with a normal fish load, or 1500 gallons with a heavy fish load UV CLARIFIER: Reduces the presence of single-celled algae by preventing its ability to reproduce, creating a healthy pond for your fish. UV lamp life is 8,000 hours EASY TO CLEAN: Backflush feature cleans contaminants in the filter, and a flow indicator lets you know when to clean CRYSTAL CLEAR WATER: Transform dirty green fish or koi ponds into a fresh, crystal clear home for your fish ADAPTERS & VALVES: Includes inlet and outlet hose adapters, bioballs, and a multi-directional valve for cleaning; OVERALL DIMENSIONS: 14"(Dia) x 20"(H)