Seachem Algae Pads

The Seachem DuoPad™ 3 pack is a dual surface, non-scratch algae pad for glass & acrylic. The melamine foam side uses micro abrasive technology to remove algae easily from the sides of your aquarium, while the durable scrubbing side enables you to attack the rougher areas of rocks and driftwood. It is effective at removing algae from scratches. It is chemically inert and does not require soaps or detergents. It's white colour contrasts against dark algae making it easier to see when areas are completely clean.

More on Melamine

Melamine foam is incredibly effective abrasive cleaner. It has a microstructure as hard as glass, but because of its open-cell structure it remains flexible. It performs on stains similar to extremely fine sandpaper. In the aquarium, it removes algae with ease by scraping with its extremely hard microscopic filaments.