Eshopps AEO19070 Square Foam Aquarium Filter, Large

Large Foam Block Wet-Dry/Sump Filter Sponge Rectangle 4 x 2.25 x 13.5 Inches. Mechanical Filter Sponge for Zoo Med's 501 External Filter. Zoo Med's Mechanical Filter Sponge is the first line of defense in removing dirt and floating debris from your terrarium or aquarium. Grabs particulates; Removes debris.