Euro Rep Desert Substrate is an easily managed alternative to sand & gravel. Where sand & gravel are used in dry situations, desert substrate is a lighter, cleaner alternative. It is made from heat treated corn cob kernels & so it is biodegradable & ecologically friendly. Being totally organic, it poses few, if any, risks to the animals it is used with, the humans who use it or the environment. Like all the "ad Vanced vivarium substrates", desert substrate combines the performance of applied technology with the responsibility of sustainable usage