[Operator]

I am not completely sure ...
The water you mention is probably used for filling car batteries etc.
I think maybe it calcifies over time ... (reaction with air or so).

The thing I was aiming for is bacteria ...
My neighbor works a the local water facility. He told me that they rotate big arms through the water in those
huge storage tanks. He once promised me he could set me up for an excursion there.
maybe it's a good time to remind him of his promise ...