I have a male betta plakat in a 5.5 gal tank. The heater is small and doesn't seem to work that well. I put the betta in the 20 gal tank along with the blue paradise gourami, neon blue dwarf gourami, red tail shark and two corys. So far, the blue dwarf chases the male betta and nudges him with his nose and brings his fins to attention. Will the dwarf gourami kill the male betta? I thought bettas and gouramis could house together. Is this not true? The male betta plakat flares and chases the paradise blue. Will the male betta plakat (sp?) kill the paradise gourami? If a fish will be dead in the AM, please answer this thread ASAP as I will need to run to Wal Mart to get a new heater for the 5.5 gal tank (since Wal Mart's 24/7). Thanks for anyone's help.