If you have another tank throw him in there for three days. Switch the decor around and throw in some smaller fish fast/smart fish like cons and tinfoils etc (fish he won't be threatened by). Let them get used to the decor and the good hiding spots. Throw him back in three days and it will seem like a foreign territory to him. I've had great luck using this method when dealing with RD, RTM, Grammodes etc. Try it, you may still be able to have a community tank.
good luck