lima, giant bumble bee, 4 line pim, great. channel or tig bad idea, so long as you are planning to keep the current tank. my 4 line pim is one of my favorite fish. always on the move not too aggressive. now that i think about it a great easy to come by fish would be a black shark. they're kind of aggressive toward tankmates but not brutal. birchirs and jag cats should be fine. my 14" black shark is always fun to watch.