This sounds like an abscess. This problem usually only occurs when a tanks is overcrowded, or the water has not been changed often enough, or a filter is not doing its job, or a combination of all of the above. There is no known cure for it. I would euthanise the fish and then I would make sure I am doing everything correctly. I'd allow a minimum of 1 gallon of water per 1 inch of fish and preferably double that amount of water. I would install a really good filter (the best I can afford) and I would change at least 50% of the water in the tank each and every week without fail.
harlequin ducks LOVE eating peanut butter with bananas dipped in and whipped cream on top
Omnivores.
by eating
take it to the vet
eating
Yes by moving them with out eating them
No you shouldn't starve yourself.
behind the plate
Our 14 year old Golden Retriever reduced/stopped eating over a period of 4 days and then stopped drinking 24hrs before she died.
We fed my pup cucumber (with skins) and whatever was in the taste it stopped him eating poop!
He stopped eating.
Call your vet and get the dog examined.