with the hump on it's head, I think it's a male. FH are really aggressive fish, usually don't stand for any tank mates, and will even beat up on it's mate. Seen it happen.
If you got an extra tank, I say put him there; or you can try to divide up the tank if your tank is big enough, and one final trick that i don't really know if it will work with FH is to get a fish net, wait for the FH to act up, then chase the bugger using your net all arond the tank, and really tire him out. Every time you catch him acting up, use the net. I can't guarantee if it will work. did work for my parrots though.
Good luck, 50 dollars ain't bad for fish like that. My brother in law paid 60 for one that's not as good looking as yours.