i'm considering getting convicts and i was wondering what type of substrate would be best i heard they like to dig so i think gravel is out of the question...what about sand? and would colored sand make any difference and another thing there aren't really any lfs around where i live but there's a petco near by so i'd probably have to end up buying it from there so if you know of any good substrates that they carry that would be even more help. Thanks