Confused and somewhat embarrassed

[jambop]

OK I have been exploring my water profile and have been given an analysis by my supplier which reads
Cl 12.5
Ca 43
Mg 3.5
Na 5.6
SO4 26
HCO3 123 mg/ml or ppm

My water calculator askes for CaCo3 and I have come across convertors that state HCO3 / 1.22 gives CaCO3 which in my case would be about 101 ppm However I came across this site below which turns things about a bit when I plug in my Mg (3.5) and Ca (43) gives 122ppm CaCO3
www.lenntech.com/ro/water-hardness.htm
... confused

 

[cire]

Your calculation is correct for determining hardness, while the HCO3 figure given is for alkalinity. Therefore, using the calculation in reverse, alkalinity will be 100.8 ppm in terms of CaCO3.

Both hardness and alkalinity can be denoted in terms of CaCO3, but HCO3 normally refers only to alkalinity.

 

[NotSure]

There's total Alkalinity As CaCo3 with this water calculator:
Brewing Water Calculator - Brewingcalculators.com

To convert Bicarbonate (HCO3) to Total Alkalinity as CaCO3, multiply by 50/61. This calculator does it for you if you click the radio button.

 

[jambop]

Thanks that is that cleared up!