The Boyu Floating Magnetic Brush is a high quality two part algae cleaning brush. This product cleans both the inside and the outside of your tank. The inner brush wipes away algae and grime build up on your tank walls. The outer brush keeps the glass of your tank clear and spotless. The two brushes connect via magnet, however if the inner brush loses contact with the outer, it will float to the top of your tank for easy retrieval. It is safe for use on glass aquariums as it will not damage or scratch the glass. It features an easy outer grip and a powerful magnet for effective cleaning.