Straight waterfall box or a biological filter and falls. Extra wide spillway for greater water aeration. Pro2000 biomatrix filter & falls 11.25 opening. Open swirl chamber for even and efficient water flow through the filter media. Mechanical and biological filtering for super clean water. Easily buried in ground to hide canister from sight. Clean once a year under normal use. Size is 2000 Gallon. Dimensions are 15 X 12 X 9 UPC Code = 025033024687