Meet “Decay”.
This picture was taken in the morning about 12 hours after feeding. She’ll be like this at any given time though, morning, evening, whatever. She can swim normally but every so often she, like, goes comatose and floats around on her back like a dead fish. Tap on the glass and she wakes right up, flips back over and shoots you a dirty look just like any other fishie.
WTF? This has been going on for over a year.
Dropsy. It is a disease of her swim bladder- the organ that keeps her afloat and helps her dive and surface. It is treatable unless she is old or very very sick.
Interesting. Some points to clarify based on Beaucarnea’s assistance:
That said, I was thinking a swim bladder condtion that manifests when Decay is asleep or just too damned lazy to put forth the effort to be upright.
Do you have any frozen peas? Goldfish sometimes suffer swim bladder problems due to some missing nutrients in their diet. Try dropping a couple of small frozen (or cooked- but these might sink) peas for her to eat.
Read this page for more information and ideas about treating swim bladder disorders.
OK. That should be fun.
You might want to change her name.
Nooooooooo! I was thinking those were some of the coolest names ever. Then I was going to ask if there were more and what those were called. So Inigo, tell us, tellus, TELLUS! 
The goldfish was “designed” by evolution to be, well, fish shaped. The “fancy goldfish” was redesigned by man to be shaped like, roughly, a fig. Needless to say, this presents some problems. Chiefly, all those fish insides are now crammed into a much smaller gut. So they don’t always work as well. Sometimes, for example, they get little pockets of air trapped here or there (not sure of the exact mechanics).
When I was working at a pet store, this is the remedy that worked for us. First, fast for at least a week. Keep in mind that it would take a goldfish around 6 months of total fasting to starve to death, so fasting for a week or so will not harm it at all. Then, feed the fish nothing but canned peas for another week or so. ONE canned pea per day, popped between your fingers as you place it in the water.
After this regimen, you’ll need to change your food to prevent its happening again. Goldfish are primarily bottom feeders. Stop feeding flakes, stop feeding floating pellets. Find some sinking pellets (they’re out there), and your fish will no longer gulp air when it eats.
Also greatly reduce your feedings. When I have goldfish, I tend to feed them every two or three days, maximum. Keeps them lean and mean. They’ll be much more energetic and bright eyed, and their home will of course be much cleaner. Also, don’t feed more at any one time than they can eat. Rotting leftovers for later grazing is NOT a good thing. If you MUST feed daily, feed only an eyeball’s-worth at a time (roughly the same volume of food as that of the fish’s eyeball); that’s all most fish can eat at one “sitting.”
When in doubt, don’t feed; overfeeding causes FAR more problems to captive fish than underfeeding. Especially when they’re living in and breathing their own toilet water. Think of that.
Sorry, “Pestilence” and “Decay” are the only two cool names. Well, and “Krypta” the plecostomas. (Yes, I was a Majesty fan until the disc got stepped on).
As for the changes to the feeding regimen, they share the tank with some neons, a cory catfish, a fistful of algae eaters and of course, Krypta. Can they handle eating less often as well? I have noticed that when I cut back on the feedings that I start running out of neons. I highly suspect the goldfish of suplementing their diets in times of dearth. The villians.
Well that’s a major problem right there. Goldfish are coldwater fish; the rest you mention are tropicals.
How serious are you about giving them an optimal environment?
