We have comet gold fish in our pond - about 4" long. All of them are great, except one. The last few days he (she?) has been lethargic and not eating. So I caught it and put it in a 2 gallon tank (with proper filtration) in the house. I can see no outward signs of disease. He's been in the house since this morning, and has still not eaten. Does anyone have any ideas about what could be wrong, and how to treat it? :o

I answered your question in the pond fish category.