If you travel enough it is not a question of IF you will ever get bad fuel… it is WHEN. And Murphy’s law will guarantee that your engine will fail at EXACTLY the wrong time… like just as you are entering a crowded anchorage on a windy day (don’t ask how we know this).
On Q we have 2 fuel tanks and never fill both at the same time/place. A good precaution… but we found an even better solution.
We installed the Filter Boss unit just after we bought the boat and have (knock on wood) never had a fuel problem since. The unit uses large Racor filters and has sensors to detect whether there is going to be a problem. It gives you a warning so you can solve the problem (by turning on the electric pump and switching to the backup Racor filter) before there is a fuel problem. You can also ‘polish’ fuel by moving it from one tank to the other while running it through the filters.
The Filter Boss people are great. They even built a custom unit for us as our fuel tanks are under the forward bunk and we had very limited space for the unit there. We understand that KTI now has updated units that are even more useful.