Do a 50% water change. Treat the tank with Malachite green @ 1/2 strength and salt at one tablespoon per 5 gallons of water. Treat the fish in a bath of tank water with Methylene blue 2 teaspoons per 5 gallons for 30 mins. Do daily 25% water changes while treating. This should clear it up. If you don't see any improvement on three days let me know.
I would ditch the pimafix, use the salt until meds arrive. Keep the water CLEAN. The MB bath is key here so that will be important the MG treats the tank. What temp is the tank kept at?
That almost looks like what was on my red terror
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