Estes PermaGlo is a fluorescent colored gravel that really stands out under black lighting! Great for securing tank decorations and adding a bit of neon flair to a more modern aquarium. 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, making this substrate simple to install into any tank. Non-toxic and safe for use in aquariums, terrariums, and planters.