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Fish/Very ill Oscar


Hi Ron!
My Oscar is three years old. He is a Red/Black Tiger. Has been very active and healthy until recently. He is in a 50 gallon tank. I just purchased a 110 gal. as he has outgrown his tank.
BUT...not moved him yet. A few days ago it seemed he was dying. He was unable to descend to the bottom of his tank. Was beginning to float on his side. We found the heater was broken and temp in tank was around 60 degrees. After much assistance (and a new heater) he has mainly recovered. (I also gave him a frozen pea with a Epsom Salt grain in it.)
THE ISSUE NOW: He is not eating since this occurred. Today has been day four (4) of not eating. He seems completely normal other than this particular problem. In addition, I never gave him feeder fish until about two weeks ago on advise of the local pet store. There are around 12 feeder fish left in the tank; and he is not interested in consuming them either! (I read where he should not be fed goldfish or feeder fish. And never will do this again.)
I am leery of setting up the new tank and moving him while he is not well.
Soooo... any ideas? Your advise would be greatly appreciated! Thank you!!!

Hi Karen,
  The fact that he is not eating is not good, but not immediately a problem -- he can go several weeks without eating anything.  

  NEVER feed "feeder fish" to an oscar, but you know this now.   Take out the remaining feeder fish.

  I do not see that moving him will cause any more problems.

  His lack of eating may be due to several things: it could be due to the heating issue, or it could be due to an intestinal infection from the feeder fish. I can't really say from here.  The key is to try to give him a stable environment and hopefully it will resolve itself. You might try feeding him some thawed frozen peas, if he will eat them, to help clear out his digestive tract (that sometimes works).

-- Ron C.
  Cichlid Research Home Page <>


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Ron Coleman


I am an expert on cichlid fishes, particularly New World cichlids. My broader expertise includes the behavior, ecology and reproduction of fishes in general. (I am NOT an expert on Goldfish). Please do not use abbreviations, such as "my GT has a swollen eye" because I don't know what a "GT" is. The more clearly you can explain your question, the better chance I have of understanding what it is that you seek. I keep fishes both as a scientist and as a hobbyist and I currently maintain about 140 aquariums.


I am an Associate Professor at the California State University, Sacramento in the Department of Biological Sciences, and I run a website, called the Cichlid Research Home Page . I also write for many popular aquarist magazines, and I was editor of Cichlid News magazine for several years. I am a scientist and I spend my time teaching fish biology, ecology, behavior and evolution and doing research on the reproductive biology of fishes, particularly cichlids. I do research in the laboratory and in Costa Rica, Nicaragua and Mexico. My main interest is understanding the evolution of parental care in fishes. I am interested in encouraging greater public awareness, understanding and participation in science.

Cichlid News, Tropical Fish Hobbyist, Freshwater and Marine Aquarium, Science, Behavioural Ecology and Sociobiology, Copeia, Canadian Journal of Zoology, Trends in Ecology and Evolution, AUK, Environmental Biology of Fishes

PhD (Toronto, 1993) MSc (Simon Fraser, 1986) BSc (British Columbia, 1983)

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