I can give you a case study, if you want. My water is a little bit softer than yours, but I just brewed an oatmeal stout in November and the information could be useful.
One key takeaway is that most calculators will tell you to over treat your water, at least for darker beers. This is especially true of Palmer's and EZ Water Caculator. Some also push a chloride to sulfate ratio that can have you over-salting your water if both of them are already high. A better recommendation is to keep one or both of those below 100, diluting your base water if necessary.
This is what I did for my oatmeal stout.
Total Dissolved Solids (TDS) Est 203
Electrical Conductivity, mmho/cm 0.34
Cations / Anions, me/L 3.0 / 2.8
Sodium, Na 21
Potassium, K 2
Calcium, Ca 28
Magnesium, Mg 8
Total Hardness, CaCO3 103
Nitrate, NO3-N 2.3 (SAFE)
Sulfate, SO4-S 4
Chloride, Cl 48
Carbonate, CO3 < 1
Bicarbonate, HCO3 59
Total Alkalinity, CaCO3 49
Note that SO4-S is sulfate as sulfur, which is how Ward Labs reports it; multiply by 3 to get PPM sulfate.
The grain bill for 12 gallons was:
2-row 16.75 lb
Flaked Barley 3 lb
Roasted Barley 2.5 lb
Flaked Oats 2 lb
CaraVienna 1 lb
I mashed with 10 gallons of water (1.56 qts/lb). The predicted color using ProMash and the Morey algorithm was 39.8 SRM.
For Kai's calculator, the step that takes more work is to calculate the color percentage from roasted malts versus crystal malts. Basically, you ignore all base malt and take the ratio of SRM contributed by roasted malts to the contribution from all color malts. In this case, I only had to include the caravienne and the roasted barley.
roasted % = (roasted weight * srm) / (roasted weight * srm + crystal weight * srm)
= (2.5 * 550) / (2.5 * 550 + 1 * 20)
= 98.6 %
Kai's calculator predicted a pH of 5.34 without any salt or acid adjustments.
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For Brun'Water, I entered the same water profile and mash size. There's then a screen where you put your recipe in, and it calculates SRM and estimated mash pH for you. Brun'Water predicted a pH of 5.2.
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So, what was the actual pH of the mash? I measured it twice with my meter (Milwaukee MW102) and both readings were around 5.48 - 5.50. I even recalibrated before the second reading, because my colorphast strips were reading much lower: 4.8 ish, which when adjusted for their assumed error is still 5.1 at room temperature. The first reading was after 15 minutes of mashing, and the second (and the strip check) after 30 minutes. My takeaways from this is that 1) I won't be using the strips anymore, and 2) What AJ Delange has been saying for a while is right -- you rarely need to add chalk to your water.