go honey or thick-lipped along with the pearls, they are a lot more friendly. Mine are very playful towards eachother at times, and at other times pick out territories but don't ever hurt eachother. I have heard only one male dwarf gourami is recommended, but for such a tank you should try to find the more rare and duller female dwarf gouramis. I would really recommend only ONE single male dwarf gourami out of all the types, i'm sorry but that means only one powder or flame or other types....although in all honesty i'm pulling this info right out of a book that i have, it's new but not my own experience with the dwarf gourami. I could imagine your tank handling two, but they will fight when they meet......on the other hand imagine how many pearl gouramis you could get! Gouramis are also my fav fish, I think there is room for a gourami in every trop tank! 
