Yes, low potassium can cause / trigger a seizure, especially if you are prone to seizures. Potassium is a major chemical substance which takes part in neuronal signal transmission. Low potassium leads to uncontrolled signal production and leads to seizure.
This thread is a it old but I found it through a search.
I'm 55 and had a first seizure 13 months ago while running. CT, MRI showed nothing. The only comment by the ER nurse (to my wife) was that I had a low potassium level.
The neurologist , however, didn't bring up anything about potassium when he checked me over a few weeks later. He couldn't find anything obviously wrong and stated that if an adult has one sezure and doesn't have another seizure within 3 months that there was a good chance they will never have another.
It's now been 13 months and no seizure. I went running 2 days after I had my seizure and most days since. With this amount of time passed, the anxiety has lessened considerably.