GRAVEL SIPHON. . Removes fish and waste from the bottom of your aquarium whilst making your water change easier removable gravel guard. Water is drawn through the pipe with the hand pump mechanism(no need to suck on tube)! Non-return valve fitted. Excellent helper to change water & clean the gravel. There is a stopper to protect fishes/plants from being sucked into the vacuum. Easy to use. Just press on the pump and water will flow from the tank into a bucket. Made of durable plastic.