Agreed. Funny
but seriously tank-kept fish cannot be released back in the wild even if native there. They can carry very different bacterial and parasitic cultures to which feral fish have no immunity. Sorry about being pedantic 
been wondering if the local aquarium will be more willing to take him in if he was a foot longer?
It doesn't get that cold in SLC in the winters. My grandmother in North Salt Lake had an outdoor pond filled with various types of Koi and goldfish and they made it over the winters. Granted her pond was in ground which helped verse an above ground for the winters.
Could do an outdoor above pool for the summer and then put it in the garage for the winter or dig an in ground pond and heat that.