tank capacity and suggesting tank mates

Question
I have a 55 gallon , with under gravel filter and 2 ,30 - 60 aqua tech filter pumps.I currently have 1 red Oscar-about a year and a half old,2 black convicts 1 male, 1 female fully grown and a 9 inch pleco. my question is how many fish can this tank hold? Am i at maximum capacity? If not are there any suggestions you can give me for more fish?Thank you very much for your time and consideration.  matt  

Answer
Hi Matt,
  I think you are pretty close to the max for that tank. In fact, I would say that you are lucky that the convicts are still there.  As the oscar gets older and larger the convicts might just disappear one day.  A fully grown oscar is 12 to 16 inches long and he won't want any company in that tank.

-- Ron
  rcoleman@cichlidresearch.com
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