I'm curious to see what others have to say on this... I added a cleaner and three peppermints initially, then added a fire red a few weeks later. The peps disappeared one by one (started happening even before adding the fire red - I don't know for a fact that it was aggression/predation though, could have been some other reason - and I only ever found 1 corpse). As for the fire red and the cleaner they've been tolerating each other ok for the 6 mths or so they've been together. The cleaner is all over the place, the fire red is a bit more cautious. The fire red is a bit territorial, does not like the cleaner to be 'in his space' and chases him off (like 4" away). The cleaner couldn't care less and no damage is done. This is a 75g.