EG DANNER MFG - PRO1000 Waterfall BoxUnit Dimensions 12 inchL x 9 inchW x 7 inch HWaterfall Width 8 inch Opening Available in four sizes - Pro1000, Pro2000, Pro 3000 and Pro5000 Extra-Wide spillway for greater water aerationOpen swirl chamber for even, efficient water flow through the filter mediaMechanical and biological filtering for super-clean waterEasily buried in ground to hide canister from sightExtra-large capacity designed to increase biological filtration.Clean once a year under normal use.