Helps change water in aquariums. Lee's Ultimate GravelVac Kit attaches directly to your kitchen or bathroom sink faucet via a long hose, so you don't have to deal with buckets or pails. Attach the ultra gravel vac directly to most faucets using the faucet adapter provider. Drain the dirty water right into the sink and refill the aquarium with ease. Twenty-five percent water changes should be performed once a month. High Quality Plastic, 25: Size: 25 ft.