The glass cleaner sera scraper XXL allows quick and thorough removal of algae and other dirt on the aquarium glass. Each set contains three different tools that are easy to change - one stainless steel blade for glass, one plastic blade for acryl glass and a sponge for soft layers - flor cleaning inside the aquarium glass appropriately and very gently. Even persistent algae can be removed without effort. 12 inches (30 cm) long.