I have had African Clawed Frogs (regular, not dwarf) for about seven years. Recently one of my oldest frogs died after having a seizure. It had a lopsided stomach where one side was bulging out and the other side was very flat. I had separated this frog from the others to prevent them all from getting sick. Now one of my other frogs has developed this same stomach condition and I am worried that it may die as well. Does anyone know what causes this and how I can cure it? Thank you