Estes Special Spectrastone Gravelis a premium non-toxic gravel designed specifically for desktop tanks, including betta habitats and other smaller marine and reef tanks. This aesthetically pleasing substrate helps embed plants and other decorations while also tying your aquarium’s interior together. All Estes products are clear coated, using 100% environmentally friendly high gloss resin. This state of the art process makes their gravel virtually dust free, and provides the best possible appearance and ease of use in your aquarium.