Estes Nature Blends Gravel is a high-quality non-toxic gravel designed specifically for basic freshwater tanks. Great for brightening up aquarium interiors as well as weighing down plants and decorations. 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