Absorption of CO2, making carbonic acid.  Boil it to remove the CO2, or
add a mineral to increase it, such as calcium carbonate (lime).

Marshall

Leo Regehr wrote:

> I must measured my kitchen tap water with a ph strip and it read about
> 6.8
> Then I measured some dw that was about 8-16 hrs old and it read about
> 5.6
> Why would that be?? What is the best way to raise the ph before
> drinking it?
> Leo
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