ethiopianbuffman wrote:if I was to do Recipe 1 for dark roasts (50% strength), I would add .19g of potassium bicarbonate to 1 gal of distilled water if I bypassed making the concentrate?
Correct. Simple recipe math here: You want 50 mg/liter. multiply that by 3.8 liter/gallon to get 190 mg/gallon, then divide by 1000 mg/g to get 0.19 g/gallon.
Stanford55 wrote: Recipe #1: 5 gallon RO water mixed with the appropriately sized Third Wave Water espresso packet yielded: 187ppm/70 alkalinity.
Recipe #2: 3.8g potassium bicarbonate/distilled water concentrate mixed with 1 gallon of distilled water yielded: >17.1ppm/50 alkalinity.
boren wrote:Are you sure about this number? It's seems off by a factor of 10 compared to other users in this thread:
I'm not Stanford55, but that sure looks like a typo - probably meant to type 0.38 g
in one gallon. If he had used 3.8 gram his Hach kit would have tested way up the scale with 250
500 mg/L CaCO3 equivalent alkalinity. (BTW, I'm not sure I understand his alkalinity numbers. Half Full
strength rpavlis should be about 25 50
mg/L CaCO3 equivalent, or 1-2 3
drops on a Hach drop kit test. )
Edit corrections: The half strength 50 mg/L KHCO3 that ethiopianbuffman wants has only 25 mg/LC aCO3 equivalent alkalinity. Stanford55 was using full strength (100 mg/L KHCO3) and I initially got the two of those mixed up.