blue gourami multi-sympton skin disease(?)

Question
  I am trying to help my mom diagnose her ailing blue gourami(~3")   Initially it appeared to be a pigmentation issue.  A white "colar" encircled the fish in the vicinity of the pectoral fins, followed by a fading of the color in front of the band. The entire head was/is very pale. There is a narrow band of normal coloration between the faded band at the pectorals and a point just in front of the dorsal fin.  Behind this point the fish is very dark, almost black.  The effect is appearance of a 3-colored fish- - light head, medium central band and very dark back half. The fish now exhibits raised crusty sores on its body.  It shows no sign of distress. He eats well and is active. There is no scraping or rubbing behavior as in common parasitic infestations. No other fish in the 55gal community tank are affected.  
  She has been treating the tank with Melafix from Aquarium Pharmaceuticals.  I see no changes as a result of the treatment.  I have set up a small hospital tank for her but need to identify the condition(or combo of conditions) to give specific treatment.  
  Please help me to diagnose or direct me to more in depth information to help identify the condition.
thank you.
Barb

Answer
Hi Barb:  This sounds like a cross between a fungal and bacterial issue.  I would not treat with Malafix... it is really great for wounds but I have never had much luck with using it to treat other things.  I would medicate with a dose of triple sulfate or General Cure... These sores are likely to spread so treat the entire tank... Also of great importance is to use aquarium salt each time you use a medication in the tank.  The salt helps the fish to breath and extract oxygen from the medicated water..... keep me posted... dave