Mag Float s powerful rear earth neodymium magnets enable the easy removal of algae. By dragging the Mag-Float on the outside of the tank the Mag-Float on the other side of the acrylic surface follows scraping off the algae with the pad. Most impressively you will no longer get wet cleaning off the algae from your aquarium because the Mag-Float simply float up allowing easy retrieval. Safe for glass acrylic and plastic aquariums up to 10 gallons. Features: No longer knock over decorations damage corals and invertebrates Mag-Float simply floats up allowing easy retrieval Cleaning Velcro pad remains free of sand or gravel thus preventing scratching Made from non-toxic ABS plastic allowing the Mag-Float to be left attached to your aquarium surface at all times Can be used in freshwater and saltwater tanks Magnet does not lose strength over time Convenient and practical for the next clean-up job