Looks like the brita may be using the same type of resins that water softening systems use, in that case like the faq states it is partially removing calcium and magnesium, but adding different salts to the water in the process which isn't really a good thing. Aside from spending the few hundred dollars on a ro system, you may have to think outside of the box a bit, possibly by contacting drinking water suppliers that fill and deliver those 5 gallon jugs for office water coolers. Maybe you could get water directly from them.
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