I'm new to using BF for building water. I use 100% RO water from the local grocery store for BIAB brewing and want to save an "RO Water" profile in Brewer's Friend. I assume I'd enter "0" or near 0 for the various ions, but am not sure what to enter for Alkalinity (speaking of "0", that's close to my knowledge level of water chemistry). Should I enter "0", and should I select "Bicarbonate" or "Hardness" in the dropdown menu? Many thanks!