sf > wrote:
>
>How water softeners work
>http://home.howstuffworks.com/question99.htm

That's much more an over simplified course on how to install a water
softener than it is about how water softeners work.

The thing to keep in mind is that virtually all tap water contains
salt. In the process of softening water whatever miniscule quantity
of salt a softener may add it's less than it removes so the net result
is that ones tap water will contain less salt after softening... and
we're talking about 10 mg or less per liter, which is less salt than
is contained in a liter bottle of sody pop that's permitted to list 0
mg sodium. Virtually all naturally ocurring water on the
planet contains salt, even rain water. Technically a water softener
can add some salt, but less than it removes. A human being can't
drink enough softened tap water to even come close to ingesting too
much salt. We get our salt from food, all food naturally contains
salt, and of course from salt shakers.