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Fish/gold fish ill?


Hi ! My daughters goldfish has developed some black patches near the base of his tail and black streaks on his fins.

Hi Doreen,
 Unfortunately I am not an expert on goldfish. For other fishes, that sometimes represents damage caused by being bitten by another fish. It could also be small parasites. The parasite which normally causes "black spot" is not harmful and the spots will go away over time

-- 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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