African toad help

I have had my little African toad for almost a year now and it just started acting a bit weird. It is floating on the top and its body seemed to be inflated, almost like a balloon. When I touched it is swam along the surface. It usually stays entirely submerged. It is in a 5 gallon tank with a whisper filter and various freshwater plants like anarachis and mondos grass. Is it okay?

sounds like bloat. http://clawedfrogs.tripod.com/id33.html

Crap. What should I do to keep it alive? I got the thing in a small tank at a department store. It came with food. I moved it into this tank about 4 months ago. I have fed it its special pellets as well as a supplement of freeze dried bloodworms. All I have in the tank is a snail and a few plants. What did I do wrong?

check you ph and ammonia levels a big water change may help