I have a Microglanis iheringi, one of the South American species and he is quite full of energy when he wants to be. sometimes he just hides, but other times like when i put a sinking algae wafer in, he acts like a puppy waiting to get a treat. i will stick my hand in and drop it near where he is, and he will dart over to it and try to fully consume the entire wafer (he is barely 2.5 inches). its pretty amusing to watch. this species doesn't grow much more than what he is now. I was sad to find him in the tank i got since he was housed with a bunch of Africans (wrong water parameters plus too aggro for the cat) that the guy that owned him was housing him with. i wouldn't recommend placing him in a tank with cichlids since he is rather small. maybe some of the smaller more laid back SA/CA would do but i am unfamiliar with SA/CA cichlids, so don't take that as solid advice. I would be wary of putting him in a tank in which you plan on breeding anything as well