So, to prevent this from happening again, I figured I would install a fuel/water separator on the tractor. I started searching for this part and weeks later I'm still looking.
Oh, for those who are thinking, "Put a separator at the pump and you won't have to worry about contaminants..." or "Why don't you find a cleaner source of fuel?", or whatever. I know, I'm on it, I'll be addressing each one of those steps, with available components, and those will do their part to prevent the contamination. It's the final link in this chain I'm having an issue with before the fuel goes in the engine. Let me know if you have any questions or recommendations. I appreciate any and all feedback. Thank you.