Blended with 6 different substrates. Reptisoil is a 4-part soil substrate mix that combines humus, peat moss, sand, and carbon to create an excellent base for a bioactive habitat. Reptibark adds structure to the substrate which resists compacting, providing drainage and aeration. Sphagnum Moss is a long lasting ingredient which resists decay and retains moisture, boosting humidity for tropical enviorments.