The perfect substrate blend for your tropical terrarium! Zoo Med’s Tropical Bioblend is composed of 6 different substrates to create a bioactive base for your habitat. Reptisoil, Reptibark and Sphagnum moss are all combined to give you a substrate that is long lasting, boosts humidity, resists compaction, provides drainage, and a welcoming home for any bacteria that will grow, to create the bioactive element of your terrarium.