A few months ago, my violet goby started losing pigmentation in small areas near his head. On each side there's an area with very little pigment. It looks white but if you look closely you can see tiny dots where the skin still has pigment in it. It has also spread to the front of his dorsal fin and there is one small spot of it near the gills. So far this pigment loss doesn't seem to have any ill effects on his health, so I'm not too concerned. I have seen a video on Youtube where a younger individual had lost much more pigment. Has anyone here encountered a problem like this in any fish? Does anyone know what might be causing it, or what I might be able to do to prevent the spread of it?
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