-Tortoise Eco Terrain: has been created to meet the flooring needs of Mediterranean tortoises, Russian tortoises and other species of tortoises found in arid environments. This substrate helps to replicate the terrain found in their natural environment. A deep layer of Tortoise Eco Terrain aids in allowing tortoises to carry out normal burrowing behaviour. Spread a level layer of substrate on the base of the enclosure, at least 5cm for juvenile tortoises and increase the depth for adults. Horsfield?s Tortoises (Testudo Horsfieldii) will require a deeper layer. Spot clean daily replacing soiled substrate with fresh. Change Tortoise terrain every 2-3 weeks. Please note if using heat mats with your tortoise these items should be placed on the side of the enclosure and not beneath.Tortoises burrow to avoid heat, placing heat mats on the base of the enclosure presents an unnatural situation.