I have one blue gourami and he is very territorial and has contributed to the deaths of two of my other gouramis because he is so nasty and beats up on them. However, the doesn't bother smaller fish (tetras, rasboras, danios, etc.) If you really want to get one, I would suggest putting it in a tank with only smaller fish, or not getting one at all. I would recommend dwarf gouramis, though, which are much less aggressive and just as nice looking.