Hi sorry to hear about your frog Here is a post I wote a while back explaining ACF bloating. Let me know if you have any questions.

A "hard bloat" is very serious. It is where the frog suddenly appears on the surface of the water and the legs and body are distended. The typical treatment is the use of Maracyn, a antibiotic, along with a salt bath. Untreated, it is fatal.

The "soft bloat" is where fluid accumulates under the skin and the frog appears like the "Michelin-man". A salt bath is the recommended treatment. It is serious, but not fatal if treated. Use one teaspoon of "sea salt" or "non-iodized" salt per gallon. These frogs are quite salt tolerant. Salt baths should be no more than 30 minutes per day until cleared.

In either case, the frog should be placed in a "hospital tank" for treatment.

Bloating is caused by a number of reasons:
* bacterial infection (regular use of the probiotic Lymnozyme will help)
* stress (provide some hiding places)
* insufficient calcium (regular feeding of earthworms will prevent this condition)
* osmotic irregularity (maintain proper water chemistry)
* overfeeding of bloodworms (don't feed freeze-dried foods to your frogs)
* incorrect water temperature, should be between 68-72(F)

Dropsy and hydrops are now referred to as edema. Bloating seems to be more and more common these days. If cared for properly, these frogs can live 12+ years.
It's difficult to explain the difference without pictures. Probably the best way to tell the difference is how the frog behaves. If it looks like a balloon and gets around fairly well, than it is probably soft bloat. Hard bloat frogs usually hang out around at the surface.

Here is a photo of soft bloat