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abweatherley 08-29-2010 06:41 AM

Question about water
Hi guys I start brewing next month (long story basically have to get my "brewery together bits at a time)

I am looking at my City water report and don't see a bicarbonate level in the report. It does however have a line in the report saying "Alkalinity as CACo3" is this the same thing.

What else would it be listed as on the report.

ajdelange 08-29-2010 11:30 AM

For pH < 9 you can consider all the alkalinity to be caused by bicarbonate. At pH 9 about 5% of it is caused by bicarbonate and hydroxyl ions come into play as well. To compute alkalinity divide the bicarbonate by 61 and multiply by 50. To be precise add 2.5. This should be done beacause it is alkalinity that is measured and bicarbonate calculated from it. Even distilled water has an alkalinty of 2.5 or so. Your lab probably didn't take that into account when they calculated bicarbonate and none of the spreadsheets do when they calculate alkalinity from bicarbonate so you can probably safely ignore that nuance.

Example: Bicarbonate 122 mg/L, pH 7. Alkalinity = 50*122/61 + 2.5 = 102.5. The actual alkalinity for this case (assuming the bicarb is all calcium bicabonate) is 101.8.

Example: Bicarbonate 112.2, pH 9. Alkalinity = 50* 112.2/61 + 2.5 = 94.5. The actual alkalinity in this case is 100.

Now where the pH is high like this the report should include carbonate ion as well so the report should read:

Bicarbonate pH 9, bicarbonate 112.2, carbonate 3.6. Add twice the carbonate divided by 60 before multiplying by 50 i.e.

alkalinity = 50*(112.2/61 + 2*3.6/60) + 2.5 = 100.5

abweatherley 08-29-2010 06:39 PM

but it doesn't have the bicarbonate level in ppm on the water report

ajdelange 08-29-2010 07:02 PM

Well that was dumb. I answered you bassackwards. So it's basically just the reverse. Take the alkalinity and divide by 50 then multiply by 61. Example: alkalinity 100, pH< 9: bicarbonate = 61*100/50 = 122 mg/L.

abweatherley 08-29-2010 08:11 PM


here is the report

Sean 08-30-2010 01:29 AM


barnyard 08-30-2010 03:21 AM

What is wrong with Ozarks drinking water? just seams like a lot easier thing to do. No diving there just open the bottle. Not being a d$%& but really want to know why.

boss429 08-30-2010 05:09 AM

I know this isnt productive but

mmm.. vinyl chloride and NDMA sounds like it will make a yummy beer...


I just didnt see that kinda stuff in my water report strange.

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