You guys must find gouramis that have been fed crack or something. I've had all kinds of gouramis together and never had any of the "killer" aggression that you have. Pairs of gouramis are just fine together. I have a pair of pearls and a pair of dwarfs in my tank now and they don't pay each other any mind. The pearls hang together and the dwarfs hang together. I've bred pearls, opalines, golds, blues (all Trichogaster trichopterus I know), and dwarfs without the aggression I keep reading about here.
