I found a goldy in a pet store. BUT... something is wrong with it, really wrong. It has some parasite or infection. Anyway, there is some sort of white

grow

on the bottom of the fish next to anal gland. It looks like a ?worm? sticking out from under the skin. The fish seems fine -- like eating, swimming, having fun... I kind of fall in love with that fish, I would like to get it and try to cure it but is there any hope for me and that goldy

Or should I just leave it alone and let it be at the pet store?
thx

))