The Aqua One Vac-A-Tank gravel cleaner is designed to be user friendly since it has a self-starting siphon model. Use the Vac-A-Tank gravel cleaner as an aid to your vital hassle-free routine water changes and tank cleaning as an effortless chore. During your partial water change, as the water is exiting your aquarium, simply plunge the gravel cleaner into the gravel whilst the natural siphoning actions of the water extracts the dirt and carries it up the tube and out of the aquarium. Key Features: Self-starting siphon model. Perfect slim profile. Designed for constricted hard to access places. Will clean your gravel of waste substances for a healthier aquarium. Enhances the health of all your tank inhabitants.