MA,

I tested my Walmart DW, and it was Zero.

Tested the first 3 quarts that I brewed on "fast" at a setting of 4, with the 
silver particles, and they were all around 11.

Tested the fourth quart that I brewed on "standard" at a setting of 3, without 
the silver particles, and it was 5. 

So ... I guess Im moving right along  ;>
    jan