cichlid died

Question
I have 40 gallon tank with 3 ( now 2 )firemouth cichlids that are about 2 inches long and a albino tiger Oscar that is about 5 inches long. Recently 1 of my firemouths died, about 10 minutes before it died it was just fine and then its gills and mouth started moving very fast, and was trying to get to the top of the tank, no matter how hard it tried it could not, then it died. Can you tell me why it died. All of the other fish are just fine. -Cameron

Answer
Hi Cameron,
 That is very unusual; however, I am amazed that the oscar hasn't eaten the firemouths.  He will eventually. That is what oscars do and they are very good at it.  

-- Ron
  rcoleman@cichlidresearch.com
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