Zoo Med Midnight Black Reptile Repti Sand is all natural substrate for desert dwelling reptiles. Pure, very fine quartz desert sand-better than silica sand stimulates natural digging and burrowing behavior. Natural safe colors with no added dyes or chemicals. Excellent egg-laying medium for many reptiles. Zoo Med Midnight Black Reptile Repti Sand will highlight the colors of all albino and pastel color morphs of lizards and snakes. Desert reptile species will thrive in this naturalistic environment. Repti Sand is ideal for bearded dragons, leopard geckos, sand boas, desert iguanas, desert and semi-terrestrial skinks, uromastix, sandfish, collard, plated, leopard, girdle-tailed, or armadillo-type lizards, soft-shell turtles, tarantulas, scorpions, and burrowing frogs. Each 10 lb. bag of Repti Sand fills a 20 gallon terrarium. Helpful Hints: When using under tank heaters place one layer of substrate carpet down first, then sand. This prevents burrowing reptiles from resting directly above heater, resulting in possible burns. Reptiles lacking essential vitamins and minerals in their diet, including calcium, may ingest their substrate in order to compensate for this deficiency. Be sure to provide your reptile with proper lighting and provide a dish of calcium powder to prevent accidental ingestion of sand. Many desert reptiles and invertebrates (i.e. insects and spiders) benefit and need access to a humidified shelter for proper shedding, respiratory functions and to prevent water loss.