I don't think it is overly cautious to protect yourself. I always sanitize the water system with a bleach solution. It is cheap insurance. We also use bottle water for drinking, but still use the water from the tank for washing dishes, hand washing etc. What really concerns me is the shower. You are breathing in the steam which is just like drinking the water! We also use an inline filter and disinfect the hose connection before hooking up. Never hurts to be careful.
Fred
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