Welcome to the board, Cazzarrella!
We had a dog that had one grand mal seizure--happened in the middle of the woods after a long day of running. Although the vets were never able to give us a definitive answer about why it occurred, their guess was that it was hypoglycemia, as well. So after that we always made sure he'd eat a snack now and then when exercising and he never had another seizure
I think for these kinds of seizures, snacks sound a lot better than valium, on so many levels.

I'm glad it works so well for your dog!