That looks really nasty and I doubt the fish will survive. You should reduce the salinity to 12-14ppt (not SG), add a polymer such as StressGuard and aggressively treat with antibiotics. In this case I would not mess around. Combine neomycin with nitrofurazone, but do not add any other medications. Try to use just those two antibotics rather than something that contains other medications. If the fish are still eating then add some Beta glucan to the food to enhance immune function. Do NOT remove the fish from water at any time including netting. Use a clear plastic bag or specimen container if you move them so they are not taken out of the water at any time.
Terry B
