Oxygen in aquarium

Question
My oscar (14") has been gulping and staying over near my oxygen inlet.  I did a 40% water change yesterday and treated the water before I added it back to the aquarium.  Is there a reason that he his trying to increase his oxygen intake?  He has not been gasping at the surface however.  The tank is approx. 35 gall.  Thanks for your help.  Kevin

Answer
Hi K.A.,
 A 35 gallon tank is waaaaayyy too small for a 14inch oscar. He needs to be in something at least twice that size.  
Is he pumping his gills, i.e., moving his gill cover away from the body and back again alot, i.e., it looks sort of like panting if a fish could pant?  If so, then he is in serious need of more oxygen.  

 Is the temperature in the tank around 80oF.  If it is warmer than that, then turn it down.  

-- Ron
  rcoleman@cichlidresearch.com
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