I bought a Britta water filter and only use the filtered water to avoid calcification of the hoses.
It works quite well so far.

I use a silver spiral against the odour in the container. Doesn't help completely but significantly

Hi. Good question. I solve it like this. I also have very chalky water and use it. Whenever I go to the hardware store, I take distilled water with me. I haven't found any data on the water and would tend to disregard it, as it isn't heated and nothing much evaporates due to the largely closed system. The water on the floor doesn't leave a white film or on my black socks. So I don't think it's a problem.