Plecostamous Behavior

Question
My plecostamous seems to be very aggressive.  He lives in a 20 high gallon tank with an oranda and a calico goldfish.  He is constantly waiting and will then attack the Oranda.  At first I wondered if he was trying to clean the oranda because we had an outbreak of redstreaks a couple months ago, but now the oranda's scales on his one side are being ripped off and some of his skin is hanging off and I can tell that it's starting to hurt the oranda.  I've got my plecostamous in a breeding net right now until I can either take him back to the store or do something else.  What should I do?  Is he being aggressive or is there something else going on?  Is this normal plecostamous behavior?  Thank you so much for your help.

Answer
Hi Ashley,
 Are you feeding the plecostomus?   Many people falsely believe that a plecostomus can just eat algae from the glass.  You need to feed a plecostomus, just like any other fish.  I strongly recommend sinking algae wafers.  

-- Ron
  rcoleman@cichlidresearch.com
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