Jules59 via PetKB.com wrote:
Hello--yes I tested the water and it is fine. zthe spinning fish is still
spinning and still hanging in there, even today. Here's another question...I
have a flying fox in this tank, that we removed from our large tank because
the other fish were attacking it and one of it's tail fins was injured (looks
like it was bitten off). We found the fish swimming at the top of the tank
with it's nose up, and it would not go down. We finally got a good look at
it and it was injured. It is still alive, but it seems to be losing it's
gold stripe. It seems rather sad, too...doesn't swim much, whereas before it
was a zoomer. I don't know what to do for him.

You already did step one. Next I would recommend a methylene Blue dip
and and maybe a little Neosporin on the affected area. Then I would
treat the hospital aquarium with Melafix or Pimafix, or an antibiotic
such as Triple Sulfa or Nitrofurazone.
I have some more information about medications he
http://aquarium-medictions.blogspot.com/

Carl