Over fed or Pregnant? Tiger Oscar

Question
I have been keeping this particular Tiger Oscar for almost 8 years.  He is in a 55 gallon tank with a Pleco and a Rafael Cat and they have been together almost the whole time (at least 7 years.) Oversized filter, twin undergravel jets and at least monthly water changes.   I have grown him since he was the size of a quarter and now I believe him to be at least 12 inches long.  I have been keeping the fish the same way since switching him to the larger tank and he has not been moved in 4 years.

Just recently my oscar started swelling at the belly.  No protruding scales, no redness and no apparant bacteria.   I haven't changed a thing other than my wife may be feeding him (a little over feeding?) Everything seems normal at this point except the swelling.   Can you tell me if this is something I can fix or need to be concerned about? I thought I knew a lot obout these fish but I am stumped.

Any help would be appreciated.  

Answer
Hi Rich,
 Oscars are egg layers so they don't get pregnant as such. It is possible that your oscar is filling up with eggs in preparation for laying them, but it is more likely that the swelling is due to too much food.  I would cut back on the food if it were my oscar.

-- Ron
  rcoleman@cichlidresearch.com
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