I dont have any experience with Red Devil's specifically. I really think they are beautiful fish and I would love to add one to my community. I tried once unsuccessfully to add a smaller RD and had to remove him almost immidiatly to avoid injury as it was plainly obvious he would have been injured bad had I not taken him out. Anyway I took him back to the LFS and Im wondering if I were able to find a large RD is there an adjustment period where they are timid when 1st introduced into a new environment because If I am to find a large one he will have to probably demonstraight that he is not to be picked on early.