Originally Posted by SpanishCastleAle
What is your mash water volume? I plugged in your numbers and got an SRM range of 15-20 SRM just from your source water. Then I entered 5 gal. mash volume and it only took 5g of CaCO3 to reach an RA of 178 and in my limited experience that's plenty. It seems I never need to go to the 'extremes' that the Palmer spreadsheet suggests. Now I just go about halfway there (whether I'm going up or down) and my mash pH is still good.
My water has almost no sodium so I have used a tiny Sodium Bicarbonate addition in addition to CaCO3 additions. But with your sodium content I'd prob just use CaCO3.
I think you plugged in my "Hardness as CaCO3" value for the "Alkalinity as CaCO3" value on Palmer's sheet. That gave me 15-20 as well. If you use the CaCO3 value of 36 ppm, my SRM is 5-10.
Originally Posted by Beerrific
The reason you have to add so much CaCO3 is because it has very poor solubility. 100ppm Na is not too bad, depending on the beer. You could always add NaHCO3 until you hit around 75ppm Na and then make up the rest of the alkalinity with CaCO3, that should keep every thing in a reasonable range.
In either case, add enough as CaC03 (or other source of Ca) to get your Ca up to at least 50ppm.
This makes some sense. I thought with mash acidity the CaCO3 would dissolve completely, but if it does not, I assume the spreadsheet is taking this limited solubility into account, telling me to add more.
My thinking is, if I go the NaHCO3 + CaCO3 route, it will be when I have a very dark beer (porter, stout, in this case RIS) that I need to balance. Since I don't care so much about sulfate levels (not going for hop bitterness here), the elevated sodium levels should not create a harsh bitterness since sulfate levels are relatively low. Does this sound reasonable?
And BigEd, you're right. I need to RDWHAHB. This has just been bothering me for a while.