The only time I've had the problem nothing would have helped. When we purchased the boat in DE the owner never really used the engine a,d heated it all winter. But they didn't have it on electric heaytt as the reverse cycel would not work well enough in DE. They used the deisel heater. That works but if you leave for work you can't leave it on and so the daily cycle of temp changes grew a monster crop of algea from the condensation
in the tank. That set us up for a seriously clogged filter bringing the boat home. When we took the filter apart it was almost solid with what looked like cookies crumbs (dead algea). The fuel tank
was pretty bad too. I've never changed a filter any other time that showed much of anything in it before or since.
In cold climates where the boat stays in the water or hauled out on the hard
(like when it's for sale) I would survey
the fuel tank
a boat. You can generally clean it with a filter service
or just drain it and dispose of it. Finding out on the trip home isn't a good time given you don't really know the boat that well.