Ok so i have a 42 bowfront planted tank. I have a 3-4" oscar and a 4" RTC and i introduced a parrot fish and some new plants etc to disrupt the oscars territory. However he wouldnt leave the parrot fish alone so this morning i got a red devil equal size to the oscar so that the oscar wouldnt pick on the parrot anymore. When i dropped the red devil in it took a good minute or two for the oscar to search him out and then the standoff began. Now my question is, after the 20 min lip locking battle and displays ended will the red devil co exist fine or should i put him in a tank by himself? He doesnt seem to care about the oscar much now that he is the dominant fish and my parrot is actually swimming around now. My oscar hasnt been damaged but if the red devil wont be satisfied i want to relocate him if i should before he damages my oscar. Thanks for your input.