Directions: Spread the substrate evenly over the bottom of the enclosure to a depth of at least 1-2"(2.5-5cm). Spot-clean daily and completely replace every two or three weeks, or more frequently if it becomes heavily soiled or wet. Small areas of the substrate can be lightly sprayed to provide local humidity control but avoid making the substrate too wet.If you are using an under-tank heat mat as your heat source do not use a thick layer of Calcium Sand as this may cause the heat mat to overheat. Â