Here is the history:  20 gal. Tank. Hanging filter rated for up to a 40 gal. tank.  Three fancy goldfish, roughly 4 inches each.  Bella, Bailey and Barney.  Had these Goldie's for 3 plus years and they have grown and thrived nicely. I do water changes once a week because I realize I should have a larger tank but I just have no where to put one at this time.  Tank had been perfect, tested regularly until two months ago when I was on vacation and the filter clogged.  When I came back I had to do a complete cleaning and even though I tried to salvage some of the water I had to go through 'new tank syndrome'.  Was tough and during this time I started having problems with Bella, a red cap (shaped like a heart awwww!) pure white oranda.  

At first it looked like dropsy, lifted scales, red gills, trouble swimming up right. Then everything seemed fine.  About a 10 days ago she's going upside down again.  SHE LOOKS ABSOLUTELY PERFECTLY HEALTHY.  No lifted scales, no red gills, she eats, she's alert and wants to even play, but she can only float upside down at top of tank.  Here's what I have tried:  feeding peas, Epsom salts in tank, bought a heater and keep the tank at 74 degrees, stopped feeding regular food, tank water is testing good and regular water changes. Please does anyone have any other ideas?  I can't bare to watch her like this but she's so healthy looking I hate to put her down.  Please help.  Loridae

Try not feeding Bella for 2 or 3 days and then feed peas.