Stay away from Sand. We donât recommend sand as a substrate for indoor Russian tortoises. It remains loose, sticks to food items and gets eaten, and it can be a major irritant to a tortoiseâs eyes. Some keepers use sand because the tortoises live on sand or dirt in the wild.But in the wild, the substrate is hard packed and weathered, not loose and sandy. Wild Russian tortoises also graze on low-growing vegetation; they donât eat directly off the substrate as they often do in captivity.ome keepers use sand because the tortoises live on sand or dirt in the wild. But in the wild, the substrate is hard packed and weathered, not loose and sandy. Wild Russian tortoises also graze on low-growing vegetation; they donât eat directly off the substrate as they often do in captivity.