How to Utilize My Water Report

Hello all.

I just called the water company and was able to obtain the following information. I tried to get a bicarbonate concentration, but they said they didn't test for that and that bicarbonate was part of the total hardness along with some other stuff. So my question is, how do I use this information with a water calculator? I'm new to all of this. What I've been doing is using RO water and treating it with brewing salts per the Water Chemistry Primer thread. What I would rather do is mix tap water with RO water and then make adjustments where needed, hopefully reducing the amount of RO water and brewing salts needed. Any insight would be greatly appreciated.

Calcium - 81 ppm
Magnesium - 28 ppm
Chloride - 50 ppm
Sulfate - 42.6 ppm
Sodium - 16.3
Total Hardness - 330 ppm
Chloramine - 1.8 ppm (When I use water strait from the tap, I treat it with K-meta)

This is actually pretty easy since all the other major ions are given. I used the Brewer’s Friend Calculator (http://www.brewersfriend.com/mash-chemistry-and-brewing-water-calculator/).

Simply enter all the ions and leave bicarbonate/alkalinity empty. Hit “update calculations” and expand the report in the source water field. You’ll see that the ions are not balanced since you omitted bicarbonate. Just select bicarbonate entry as alkalinity, enter the imbalance (4.74 in your case) and select mEq/l as the unit. Click update and you get a balanced water profile with about 286 ppm bicarbonate.

Kai

Perfect!! Thanks Kai.

What matters to a brewer is the alkalinity, not the bicarabonate though they are approximately related by a simple formula as long as the pH is below about 8.

IF the numbers you were given are all from the same sample (i.e. not averages) and
IF they are all accurate and
IF there are no unaccounted for ions present in appreciable quantity (Nitrate, iron, potassium, strontium, fluoride, phosphate...)
Then
The alkalinity would be about 235.5 ppm as CaCO3 and the bicarbonate 290 mg/L were the sample at pH 7

These change to alkalinity 236.2 and bicarbonate 284 at pH 8.3

And if the pH is 9 alkalinity is 236.4 but bicarbonate is 259.8
If you are on a well at pH 6.4 (that's what mine delivers) alkalinity would be 233.3 and bicarbonate 290.3
Thus the alkalinity stays pretty constant but the bicarb can vary quite a bit. That's why we use alkalinity.

If a spreadsheet or calculator doesn't ask about the pH of the water then it is doubtless using the bicarb = 61*alkalinity/50 approximation. This is, as the numbers show, OK unless pH gets high.