Poor thing has been like this for about 2 or 3 years. But seems more swollen this summer than last. Swims and eats ok. He's really puffed up and looks like he might pop any minute. There's a pic of him next to a normal fish so you can compare them. A bit of research tells me there's something wrong with his swim bladder or kidneys. I hope he's not suffering. Just don't know if there's something I can do or not.