The Exo Terra Sub Stratum originates from the mineral-rich foothills of Japan's Aso Volcano. This natural volcanic soil, comprised of andesitic and rhyolitic tephra, boasts abundant nutrients, perfect for nurturing vibrant plant life within bioactive planted terrariums. Its porous composition facilitates excellent drainage and aeration, fostering robust root development. The Sub Stratum's crumbly, lightweight structure fosters a thriving community of beneficial nitrifying organisms, establishing a self-sustaining terrarium ecosystem. Its active biological processes efficiently decompose organic waste, ensuring the terrarium remains clean and conducive to health.