Originally Posted by lockwom
Your original recipe includes both chalk and baking soda. I'm interested in brewing this beer as closely as I can, but instead using only pickling lime to increase alkalinity, keeping sodium levels significantly lower. This chalk approach generally follows the advice of Martin Brungard, and I think even derives from some of your experiments regarding solubility of chalk.
The recipe is what it is. I checked my notes and I have even added chalk and baking soda to the sparge water. It can be argued that those two salts should be omitted from the sparge water, but I was following a purity law philosophy that if any water treatment is done it is done to all water. Technically chalk doesn't conform with the purity law unless it is dissolved with CO2.
Ever since I suggested the idea that pickling lime could be used as an alternative to chalk or even dissolving chalk with CO2 it has gained quite some popularity among some water experts. My experiments have shown that there are issues with chalk but those issues are not regarding flavor but regarding its effectiveness in raising pH. In many experiments I have shown that the utilization of chalk is about 50% and as long as your water calculator or spreadsheet get that correct there is no issue with using chalk. I actually prefer using chalk over pickling lime when it comes to building water. It's safer to handle. My work has shown that there might be a limit by how much chalk is able to raise the pH but we also know that even very dark beers don't need nearly as much alkalinity as we thought they would.
So I'd go with the shown water treatment first and make modifications on subsequent batches.
I don't think that the Sodium level is overly high. It's about the same level they have in Duesseldorf and I doubt that the brewers there remove sodium from their water.
I'm leaning toward an "Amber Malty" profile like Brunwater, when comparing your previous chloride and sulfate levels.
The recipe comes with a water profile, so why is there a need to take a different target water profile. The water profile I'm giving tries to emulate the Duesseldorf water. With that water you should be able to get the desired mash pH. It worked for me but there might be variations in the base malt DI-water-pH that may throw this off. But you won't know that until you dough in.