Desgined for planted aquariums and aquascaping, Controsand by Ultum Nature Systems is a natural substrate blended for freshwater aquariums and terrariums, Controsand is safe for fish/invertabrates/reptiles. Controsands can be used alone or in combonation, layered to create different scapes. Cooler in tone and will pair perfectly with stones such as Seiryu and will also provide a neutral contrast to darker rocks.