Copy/pasted from Yahoo answers:
"This sound like classic swim bladder disorder!
Fast your fish for 2 - 3 days and then feed frozen peas that have been thawed and slightly smashed. Essentially, this is a fish laxative! Feed twice daily until the fish improves. If the fish doesn't improve in 3-5 days, you should consider increasing the temperature of the tank and adding aquarium salt. 1 tsp per 5 gallons is fine. Aquarium salt is available at just about any pet store that sells fish. (Do NOT use table salt!)
Swim bladder disorder is frequently caused by fish gulping air at the surface of the tank whilst eating. For this reason, feeding slow sinking pellets or granules for goldfish is a good choice. Bubble-eyes tend to be mid to bottom tank feeders. Sinking pellets would be my recommended food.
Make sure you have large, smooth gravel substrate in your tank with bubble-eyes. You also need to be sure you don't have anything in the tank that can rupture their eye sacks! Marbles are a great choice for these fish".