sanitizing the water tank.
There are some nasty critters living in most untreated water sources. Things that cause short and long term discomfort and disease. First, your well has no residual disinfection, so anything in the trailer tank is just going to continue. Second, it's hard to believe you only come into contact with tank water in the shower. How about washing hands, cooking, brushing teeth, etc? All of there are exposure routes. Besides it's relatively easy to sanitize the RV tank. Just fill it with clean water, put in 1-2 cups of bleach and go for a drive with the trailer. Leave the bleach water in the tank for an hour. Drain the tank, and flush at least once with fresh water. Run all the faucets with the bleach water and the flush water. You may have seen threads on this forum about the tank and not being able to remove all the water. that's a good argument for flushing the tank a few times.
2009 FF X-189 FDS
2011 Chevrolet Z-71 LTZ 4X4 p/u.
Reese WD hitch
Patient and understanding wife