Could he have possibly gotten a piece of food lodged in his thoat and choked to death? I have heard of this happening before, but you can usually see the food hanging out of the mouth.
It's just really unusual for a fish die as sudden as yours did. I'm sorry for your loss.
On a side note, if you'd like to stop getting shocked all of the time in your condo, then buy a humidifier. If you have a more humid environment, then you have less static electricity and it will also lower the evaporation rate of your aquarium.
HTH