Ion-free water for human consumption?

[Bernard Murray]

In article <541j0s$s37 at boursy.news.erols.com>, gunz at mail.erols.com says...
>
>Never use demineralised water or water teated by reverse osmosis for 
>brewing, there are tons of minerals in good water that you can't get from 
>hops or barley. Any good tasting beer starts with GREAT tasting water!
>                                                                      Jim
>

..and many consider Guinness from the Liffey to be a prime example.

		Bernard