Fish are often described as having scaly burnt skin. This condition is generally due to the local water municipality doing a “chlorine pulse”. Since the chlorine has also hit the gills, the fish need to be treated by heavy aeration. Dropping the temperature also helps.
This condition is rare. At the chlorine concentrations that do this most fish simply die. This condition is also easily confused with slime coat syndrome. If one finds a fish like this one should also treat for slime coat syndrome. Here is a link to that syndrome:
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Aquarium Science Website
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