Badgers, they seem to do fine in systems which are 100+ Gal., of course their suitabilty has alot to do with the actual dims. of the tank as well as the Volume. Mine and I have three (two full size) and one baby(6" or so) seem to do quite well, but they do have a tendency to knock things around abit. So if the old fallen rock syndrome isn't an issue for you then I'm sure you'll enjoy the heck out of one as I do.HTH..David