An Ethical Dilemma - Would You Return This Fish?

[daizeUK]

The fish is Mickey, a male platy who I've had for over a year.
 
To give a bit of backstory - Mickey was originally bought along with four female platies who were intended to be his happy harem.  Things all went pear-shaped when one of the females turned out to be male, another was sterile and the other two were producing more babies than I could manage.  Mickey ended up sexually harassing the sterile female to death.
 
For the last few months he has been separated from the females in my 120L tank where I was hoping he would form a peaceful fraternity with other platy males.  No such luck - Mickey murdered one male with constant bullying and is now harassing another young male out of apparent sexual frustration.
 
I want to move the other males out of his tank before he does any more damage but this leaves me with a dilemma.
 
Ideally I'd like to take care of Mickey until he dies naturally but I know that platies are social creatures and Mickey won't be happy on his own.  My only other option is to return him to an LFS.  The problem is that he's now quite old.  Judging by the elderly appearance of the remaining two females he came with, I wouldn't expect any of them to last more than a few more months.
 
 It feels unfair to let somebody else unknowingly buy a fish who is already nearing the end of his lifespan - and an unexpectedly aggressive fish, at that.
 
What do you think would be kindest?  Keep Mickey in his familiar, cycled home for the remainder of his life with no other platies for company?  Or let him take his chances with a new home and unsuspecting owner?

 

[fluttermoth]

I'd keep him on his own. Although platies are social, they not true shoalers, so being on his own won't be as bad for him as it would for, say, a tetra.

I have a similar situation with two tiger barbs that are the last of a large shoal. I want to sell the tank they're in but, as they're seven and nine years old, I don't feel I can pass them on to someone else. And I don't want to keep tigers any more, so don't want to get any young ones. So I'm stuck with them until they pass on!

 

[TallTree01]

Yeah I agree, keep him on his own. Solitary confinement oughtta teach him a thing or two about being nasty.

 

[Mamashack]

I once had a juvenile male platy who was a bit of a bruiser and I ended up putting him in with a male betta. They tolerated each other well with the betta occasionally putting the platy in his place. Have you another tank like that you could move him to? Then he'd have company without being top-dog if that makes sense.

 

[daizeUK]

Thanks everyone!
 
My heart was telling me to keep him so it's reassuring to hear it's the right thing to do.  I know that often an owner can feel a misplaced sense of obligation to their fish while an outsider can see that it would be better to return it, so I thought I'd better check with you guys!
 
That's true about platies not shoaling so I guess he'll be fine.  He will have the company of other species in the tank.
 
I tried and completely failed to catch any of the young males in the tank this morning so I guess they will have to put up with Mickey a while longer!

 

[noobgamers]

its a shame you dont have a group of mollies or swordtails becasue he will probably socialize with them bu they would pu thim in his place if he tried anything otherwise keep him just not with other platys

 

[star4]

I would keep him on his own with some other none livebearer fish. I have quite a few odd numbered and single "shoaling" fish  all in one tank, they are quite happy.