How long to keep potable water in holding tank

I'm the same as most, sanitize system in spring and and don't drain until I winterize. When the camper sits for several weeks I do run the water once a week, mainly to keep traps from drying out. The one thing I'm super OCD about is the cleanliness of my hose I use to fill as well as the filler valve. I also flush both for a couple of minutes before filling the tank.