Hi and welcome, There is some great advice here and as long as you are prepared to follow advice as best you can then you should have a happy healthy tort for many years, Sterilised topsoil without any additives/fertilisers etc would be best, I get mine from Homebase but you will probably know far more about different topsoils than me!I will be changing my substrate to top soil and will be spraying him with luke warm water like I do with my other reptiles