Palmer told me at NHC that he was shooting for September 2013. Don’t know if that’s fact, but I might as well pass it on with a disclaimer. 
Everyone loves Bru’n water but i hear people saying that they add the most minimal salts. My question is: if you are trying to mirror a profile (malty brown for ex) on this spreadsheet you aren’t going to be able to achieve that without adding multiple different salts, right? Especially if you are starting with RO water you wont reach the target with cacl alone.
Maybe, maybe not. I don’t think you can generalize it.
The salts added to your brewing water are dependent upon the flavor character you are looking for in the finished beer. Excepting for calcium and bicarbonate, the rest of the ions are generally added only for their flavor contribution. There is no reason why brewing with calcium chloride alone can’t produce a good beer for some styles. As the mash acidity increases, there could be a need for some alkalinity. But there is little need for anything except the calcium in the mash and wort.
Its when you are interested in incorporating other flavor contributions that more mineral salts will be needed. Brewing with only RO water and calcium chloride is espoused by AJ Delange and he is a notorious fan of chloride. Conversely, Colin Kaminski is a huge fan of sulfate. I sat between Mr. Chloride and Mr. Sulfate at the Water Panel in Seattle and that was an appropriate position for me. I feel there are definitely times when either of those ions are desirable in brewing. In addition, I feel that there are nuances that low levels of Mg and Na can produce. That is why you will find that the color-based profiles in Bru’n Water include those minor additions. But, a brewer is free to revise the relative levels of any ion based on their taste preferences and mineral availability. In the end, the only thing that will matter is the calcium content and the pH of the mash.
Enjoy!
That summed it upnicely, Martin.
Martin,
Can you expand on the nuances you find from Mg and Na? I have been going super simple lately cause I dont’ really understand the water stuff past the basics so I use just some calcium chloride or equal parts calcium chloride and calcium sulfate with lime or lactic acid where appropriate. what styles, or characteristics would be highlighted by a little more Mg or Na?