One of our two goldfish has been having some trouble recently. A lot of swimming near the top. We have changed out part of the water a number of times. Per one recommendation, we gave it some time (about 15 minutes) in saltier water and that seemed to help. It has now been swimming somewhat slowly at a more normal depth but the leading edge of its top fin now has a very thin black line for its entire length and the the end of bottom part of its tail fin has some black on it, almost like it is shriveling up. Will keep doing the water changes but any suggestions are appreciated.
Thank you
I previously posted this on a different forum but did not receive a reply. Amount of black is increasing in the last week.
