I do have an RO system already....9:1?! Wow...wouldn't that be each of my numbers / 9?
Actually, by 10. That's going to get you down to "soft" water.
That seems like not enough.....
I assume you mean not enough minerals. It is indeed enough for most beers. If you need/want something special such as the crisp minerally taste of an Export or crunchy quality of a Burton ale then you can always add salts.
Maybe I should know what I'm shooting for here....is there a pretty neutral profile to shoot for before additions? guidance?
In the Stickies for this topic there is a water Primer which is intended to get you started with water treatment and it covers most if not all styles pretty well. It's based on what seems to be a big secret: the softer the water the better the beer. Universally applicable? No but in many cases using soft water will get you a good beer. So the Primer recommends starting with soft water (such as you would get with a 9:1 dilution) and addition of calcium chloride to get the calcium level up to where the yeast are happy etc with the added benefit that chloride, up to a point, is generally a good thing. An important part of this is that you don't want to rely on calcium to set mash pH. It takes too much of it to get the drop you usually need so use of sauermalz is recommended. What I really hope people will do is buy a pH meter and use it to tune their mash pH by the use of sauermalz or lactic acid or, for British beers, CRS (a blend of hydrochloric and sulfuric acids).
Sulfate I leave entirely to the taste of the brewer. Add as much as you like but start low to see how the beer is with little or none.
Seems like 2.5 or 3:1 might be about right for UK beers.....
Possibly but you will have more control over what is actually in the water by starting with a "blank sheet of paper". So. Cal. is not known for great tasting water. Your metallic flavors probably do not come from the hardness but quite possibly from high levels of iron, manganese... A high level of dilution will cut those down as well as the other ions.
A lot of people make not so great beer by trying to over engineer the water. It should be a KISS process unless you are really really conversant with the chemistry. There are spreadsheets and websites out there that will lead you down the garden path. Start KISS and grope for what's good in the same way you would experiment with the amount of fenugreek that gives you the best Bratwurst recipe.
WRT bicarbonate ion concentration: divide alkalinity by 50 and multiply by 61 to calculate bicarbonate.
