I don't. It comes from the ground and I keep it in a container for a couple of weeks. I keep my sourdough starter open in the same area for a similar reason: I

I don't. It comes from the ground and I keep it in a container for a couple of weeks. I keep my sourdough starter open in the same area for a similar reason: I want to come in contact with local bacteria. Over time it builds up my immune resistance to things in that area. I don't go different places often (to minimize fossil fuel output), but I imagine when I do reloacte I'll have to start with sterilizing water for 90m as you recommend, then slowly start adding local water to introduce my immune system to the region.