I agree about the sand not being safe for the same reasons listed above. I have been working on plans for an indoor grass area though. Im thinking of growing in a long shallow plastic tote like the ones that fit under the bed. I will have to steralize the dirt. Theres only a few more things Im trying to iron out about what kinda grass I want to use and I have to make sure that what I choose is 100% safe. Im also trying to figure out the best way to pack the dirt in so that if my hedgie is playing the dirt isn't going to be airborne.