My alkalinity is pretty low as well. My water is very low in minerals and alkalinity, as follows (ppm):
Ca - 0,9
Mg - 1,6
Na - 0,4
K - 0,3
HCO3 - 11,6
SO4 - 0,1
CL - 0,1
NO3 - 0,1
I use Brun'water supporter's version for water calculations.
The point is: I am doing full volume BIAB and my...