The problem with the lime is that it is very strong and requires careful dosing and measurement. You have to have an accurate scale that reads into the tenths of grams. One way around that is to measure out 1 gram of pickling lime and mix that with 100 mL of water. Then you can add the lime dose more accurately by measuring out a liquid volume. For instance, 10 mL of solution provides 0.1 gram of lime.
OK, I'll switch to using pickling lime. I do have a scale that measures tenths of a gram.
It does look like a little more alkalinity is needed in that mash water to keep the pH from falling too low. A room temp mash pH of 5.2 is on the low side of the range. I find that moving to 5.4 produces a better beer.
Adding 1.2 gr pickling lime brings estimated mash ph to to 5.3
, calcium to 86, alkalinity to 190, and RA to 118.
Adding 1.8 gr brings the ph up to 5.4
, calcium to 110, alkalinity to 251, and RA to 162.
I assume I should give ph more priority over the other parameters and should use 1.8 grams?
The check box on the Water Adjustment sheet is intended to be used in cases like this, where chalk and lime are used to add alkalinity to the mash. But since sparge water has to have low alkalinity, you don't add the chalk or lime to the sparge water. In order to keep the overall calcium content of the wort at a level similar to the mash water, doses of gypsum and calcium chloride are calculated to provide that same calcium concentration in the sparge water. If the mash water calcium concentration is at the lower limit (ie. 40 to 50 ppm), then you should click the box to keep the calcium up in the overall wort. If the calcium concentration is already high in the water, then there is no need to raise the calcium concentration up in the sparge water. Don't bother with the box in that case.
Thanks. When I dilute my tap water it brings the calcium to under 40, so I'll be sure to check the box.