The Seachem DuoPad is a professional quality dual surface, non-scratch algae pad for glass and acrylic aquariums. One side is made with melamine foam, which utilizes micro abrasive technology to effortlessly remove algae from the sides of your aquarium. Melamine foam is an incredibly abrasive cleaner with a microstructure that is as hard as glass, but the open cell structure keeps it flexible, allowing the pad to efficiently remove caked on algae from minuscule surface scratches on the aquarium walls. The second side is textured and durable, making it perfect for scrubbing even the rougher grooves of rocks and driftwood clean. Chemically inert and made without the use of soaps or detergents, Seachem's DuoPad will not leave any negative impact on your aquarium. The white color makes spotting leftover algae simple, allowing you to keep scrubbing until an area is fully clean.