I agree a little more information would help, however you could start with a salt bath. One gallon of aquarium water in a bucket and disolve 4 teaspoons of aquarium salt (API) sells it. Put the fish in the bath for 20-30 minutes. It helps the healing process and kills any parasites on the fish. Is the fish eating? That is also a sign of fish health.
Looks like a nice Acei you have.
Good luck.