oscar loosing scales

Question
we just came off of our Christmas vacation and my wife notice that one of the Oscars lost all of it's scales and the skin between the fins is gone and the fish is staying at the bottom of the tank, it is not eating, it seems to be happening to our other Oscars also, before we left on our 4 day vacation we put a couple of those 7 day fish food in the bottom of the tank,[ we have 4 Oscars in a 55 gallon tank, we have been having them for 2 years] could this food be the cause of the fish loosing it's scale? will the rest of the fish loose there scales? or is this some type of disease that we need to add something to the water to cure the fishes...thank you

Answer
Hi Lambert,
  It is possible that the feeding cubes are a problem but that seems unlikely.  In any case, you should do a large water change (25%) today and then again tommorrow.  If it was the cubes the problem should clear up.  

  Alternatively, it is possible, and even likely, that one of your oscars is beating up the other.  Could this be what has happened?  

-- Ron
  rcoleman@cichlidresearch.com
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