Re: sanitizing your Fresh water tank
You should sanitize when the rv is new and at the start of every season. Use about a half a cup of bleach and fill the fresh water tanks with water then run the dilution through the taps and let it sit for 6 hours or so then run the rest of if through the taps. You can then do the same but with vinegar and water then fill and flush with clean water. As far as from the rv sitting for a week or 2 you should b good. I do however run the hot water long enough to flush the tank before turning the water tank on.
"Another Day In Paradise"
2011 Ford F150 S/Crew Ecoboost HD
2012 Jayco 33RLDS
2013 Four winns h180 ss