At prep time for every trip, I sanitize my fresh water tank. I hook up my hoses - it takes two from the hose bib, but before I hook the end to the bib, I pour in a 1/4 cup or so of bleach into the end of the hose. Onto the bib it goes, and I slowly open the valve. The water mixes & pushes the bleach into the tank. It's a pretty strong dose through the hose, but just about the right sanitizing mix after filling the tank.
After running bleachy water through the lines, I let it set while draining the tank. Those lines are flushed after the tank has been filled a second time.
The hoses have lasted for years, but I suspect they, too, will die someday. Might be after I do... then I won't care!