White Cotton Balls in Oscar tank

Question
I just noticed that my 20 gallon tank had 2 white cotton balls about the size
of a nickel floating in the top.  My 2.5 year old Oscar fish is the only fish in
the tank and he is about 9 inches long.  Right before I wrote this, I noticed
that there is another ball in there for a total of 3.  I don't know where it's
coming from.  What is it and what should I do?  

Answer
Hi Donette,
  Hmm... that is very peculiar.  Are you feeding him feeder fish?  If so, at the center of each "cotton ball" is a rotting decaying feeder fish. You need to remove those right away.

(They aren't eggs or anything like that in case that is what you were wondering).

-- Ron
  rcoleman@cichlidresearch.com
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