It is possible depending on the species involved and space available. But those two factors are incredibly important.With clowns, is it "ok" or "do-able" to house more then one species in a tank? for instance, having multiple separate nems for hosting, and 4 fish total. 2 separate species to have 2 each (example, 2 being maroon and 2 being helmets) would they pair with their own? Would you end up with one larger group where you'd have 3 males and one dom female for the whole tank? would there be too much aggression for trying to have 2 pairs in one set up?