Aqua Natural Shadow Aquarium Gravel 9.07kg 20lb is an attractive natural, dark grey river stone with a beautiful shine which creates beautiful aquascaped aquariums. The gravel is 100% natural and is naturally round and smooth by geological forces. The Gravel can be used for a variety of projects such as aquariums, reptile enclosures, hermit crab enclosures, terrariums and much more.