That's what I have in my 320g (see my sig). The pbass sometimes (maybe once a week) get a little active right after the lights go out (circling each other, flaring gills and sometimes charging each other) but no damage is ever done. They are the best of buds otherwise. It doesn't seem to bother the rest of the tank much but they are only about 10" each. Hopefully it won't be a problem when they are twice the size.