a 30 gallon is gonna be pushing it for a 4 inch tort, i think. after an initial stint in a 10-gallon while he was still tee-tiny, my redfoot moved into a 30 gallon long. while he was still in that infant redfoot "hide and nap all day" phase, that was just dandy, but now that he's pushing around 5 inches or so he's becoming more and more active and i hate seeing him in such a small space. before you call be a bad tortoise momma, though, i have a big plastic 3x5 foot sandbox that i'm hoping ot have all ready for him to move into this weekend. i can't wait to watch him explore his new place!
one more thing about aquariums -- i've read that housing with see-through sides is a no-no because it stresses them out, and they'll perpetually dig at the sides, unable to grasp the concept of transparency.
i have to disagree, at least in my case!
junior only very rarely digs like that, and it's only if he's riled up and wanting more food or attention -- he quickly settles down once i let him out for a walk or refill his food dish. otherwise he seems quite content and interested at times to sit and watch the world through the glass. he'll sit and watch me on the computer, or watch me watching a movie. on one occasion, my boyfriend accidentally pinched my toe rolling back in the computer chair, and my "OW!" brought him running out of his little hide to see what was wrong.