my oscar is acting very wierd

Question
i have 55 gallon tank and a oscar that is 12in long.  Also in the tank i have one plecostomus 12in long.  I cleaned the tank 4 days ago and yesterday my oscar started moving all the rocks and twitching and opening it's mouth real wide and hitting the glass and it's rectum is sticking out but it doesnt look like a worm.  What could be wrong with him.

Answer
Hi Gidget,
  It is perfectly normal for an oscar to move all the rocks, in fact, it is abnormal if they don't.  Oscars move rocks because they are thinking about making a nest. He is hitting the glass to protect his "territory".  

-- Ron
  rcoleman@cichlidresearch.com
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