um.... I wouldn't have a clue. dry clay can work it just needs to be powdered up. I guess from your local plant store/ building place? just don't get potting mix or anything that has addatives. as these can be bad for the birds ( but good for growing plants) you could look around your area? sorry Im not from the USA so I don't really know about the dirt situation over there. yes they are very different, and they make great pets, and they get tame real quite especially if you arm yourself with treats haha