i have two groups of micros and so far the 2nd group i have were living with my pair of oscars for a few months and they left them alone, except for when i would feed them then they would start getting a bit rough with the oscars. i also had an L014 in the tank with them and they left him alone too, never bothered him once. i'd say the only thing they ever go after are feeders but i'd never rish having permanent tankmates with them. in my experience the only tank mates they should have are other micros.