Hi there. I had 2 small goldfish. One has just died . I think it was bacterial as his fins shredded and the pet shop gave me melafix which did nothing. The other was totally fine . Fins and tail perfect. Few weeks on loads of water changes but hes staying at the top of the tank now and sometimes when occasionally swimming down he turn over loosing his balance. Hes not looking for food and when food is put in hes not interested . Could this be a bacterial infection starting poss from the other fish? I'm not sure how to treat or what I'm treating. Going to do small water changes each day this week. Thanks for any help. I know people give peas for swimbladder but he wont eat them and wasnt sure if a swim bladder treatment would help... would any treat a poss bacterial infection too?