The Protean 400 System. A true high performance all-in-one (AIO) filter system. It has the powerful Sump Buddy 40 skimmer built in. The versatility of being configured as either a Refugium, Berlin, or Plankton type sump. Specifications: * Dimensions: 28"x10.5"x16"x1/4" * Capacity: 20 gallons * Skimmer: Powerful 350 gph Downdraft II technology Sump Buddy skimmer build-in. 23" High * Mechanical Filter: 1- micron filter bag Features: * Constant water level skimmer compartment & bubble trapping dividers * Probe & Heater holders * Tank Sizes: up to 150 gallons * Pictured with Optional 13W Refugium Light FixturE, Protein Skimmer Pump, and Return Pump.