I have a 55 gallon heavily planted tank with four gouramis: a pearl, a dwarf flame, a regular honey, and a red honey. The trick is to have LOTS of plants, especially floating ones. You also need other fish to act as dither fish. I have a school of about 12 harlequin rasboras, 6 cherry barbs, 5 siamese algae eaters, 4 flying fox, four kuhli loaches, a leftover zebra danio, a few otos, and three mountain minnows. If something interesting starts going on in the tank, everybody rushes into the fray. This sort of breaks it up in a hurry. I've never had problems with the otos bothering anyone, of course with all the plants they have plenty of algae. I also throw in some sinking food for the kuhli loaches and the otos (and everyone else) eats that too. The gouramis chase and squabble occassionally but nobody ever gets hurt. I read that you have to have several of them, that way the harassment is spread around. I was actually thinking about adding another pearl. They seem to be the most peaceful. The little honey gourami seems to be the bully. Pretty funny to see him chasing away the much larger pearl and flame!