I used to be cautious about how much water we carried, but our engines don’t seem to notice much difference. We stretched our home water as much as possible, starting with a full tank on longer trips, and worked it well down before adding the next fill. I learned to be vigilant thereafter when I once filled at an older campground near Ft. Hall upon arrival without tasting first. It took weeks to be rid of the awful stuff and its lingering odor.
After that I not only check water before filling, but use a handy, portable On The Go brand softener as an effective filter. It’s also good here at home for rinsing the cars after washing, to minimize water spotting.
Joel