Undergravel Filters 30 or 40 X-High

Easy to installHeavy duty injection-molded designBiological and mechanical filtrationUnique design permits uniform flow across the entire aquarium - no other undergravel filter performs as well. Includes fish protector on the flow spouts and a raised tube connector to keep gravel from falling beneath the plate. Comes with airstones and air tubes.Tank Size (gallons)Plate Size?Tank Size (gallons)Plate Size1019" x 9"?50 or 6534-1/2" x 16-1/4" (2-plates)15 or 2023" x 11"?55 or 6046" x 11" (2-plates)20 or 2929" x 11"?70 or 9046-1/2" x 16-1/4" (2-plates)30 or 40 X-High36" x 11"?125 or 13569-3/4" x 16-1/4" (3-plates)