so here's the deal I have a mixed 220 with 2 sevrums, both male about the same size. 1 a red spot the other red shoulder. The red spot is overly aggressive with the other so I removed him and reintroduced about week later with the same results. He's fine in my 45 corner for now but long term want him back in the 220. What are some things I could try to ease the aggression?