A few days ago, I noticed my beautiful Ryukin Goldfish, Pete, wasn't doing so well. He hasn't grown much at all, and may have even gotten smaller. And then he managed to get stuck to the aquarium filter... a bizarre incident that I think injured him internally... he didn't appear to have any scales missing or scarring.
He's always had swim bladder and digestive issues, and I always made sure his water was perfect (with a testing kit for Ammonia, PH, Nitrates, etc), and I changed his water regularly. He had aquarium salt added, and was fed sparingly and given shelled cooked peas and Nori on the suggestion of internet forums and also a fish expert I know.
He has a 10 gallon palace, and was well taken care of, but always seemed to be a little off.
He's so weak that he's just resting on the bottom of his tank, and I don't think he'll make it until tomorrow :(
It's silly to be sad about a goldfish, but he was a lovely lively happy little guy and made my days brighter.
EDIT: Pete is gone now. I will likely bury him this weekend.