Does this water report look weird?

From Ward Labs:

pH 7.3
Total Dissolved Solids (TDS) Est, ppm 179
Electrical Conductivity, mmho/cm 0.30
Cations / Anions, me/L 2.7/2.8

ppm
Sodium, Na 7
Potassium, K 2
Calcium, Ca 37
Magnesium, Mg 6
Total Hardness, CaCO3 118
Nitrate, NO3-N 8.2 (SAFE)
Sulfate, SO4-S < 1
Chloride, Cl 16
Carbonate, CO3 < 1
Bicarbonate, HCO3 97
Total Alkalinity, CaCO3 80
Total Phosphorus, P 0.47
Total Iron, Fe < 0.01

Is it unusual to have water of this hardness with this high of a pH? I assumed the bicarbonate content would be higher with this pH?

There is no correlation between pH and hardness. Don't worry about it. The water is pretty nice. The primary concern is with the alkalinity. Learning to acidify and neutralize that alkalinity will be a good skill.

My city water has bicarb of 212 and pH of 8.5.

Radegast said:

Is it unusual to have water of this hardness with this high of a pH? I assumed the bicarbonate content would be higher with this pH?

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While there is a correlation between bicarbonate and pH but it is not what you are thinking of. pH depends on water treatment that has been by your water supplier. You don't have to worry about it.

Kai

There is a direct correlation between hardness and pH (the lower the pH the higher the hardness) at equilibrium but this water is not at equilubrium (it is super saturated with respect to CO2 and undersaturated with respect to lime). Few water samples out of the tap are at equilibrium. One can tweak hardness and alkalinity all over the place in order to achieve various goals (usually protection of the infrastructure). Thus your report is not unusual in this respect. The nitrate is a little high but nothing to worry about.

Unfortunately, AJ is quite incorrect. There is NO relationship between hardness and pH in water. One cannot even make that assertion for the mash (which I believe is what AJ is actually referring to) since alkalinity can sneak in there and confound the correlation.

mabrungard said:

Unfortunately, AJ is quite incorrect. There is NO relationship between hardness and pH in water.

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You don't mean that (the part about there being NO relationship between hardness and pH - the first part is, alas, all too often true). The attached chart shows the relationship. pH and hardness are both linear (nearly) functions of the log of the partial pressure of CO2 and, this, hardness is a (nearly) linear function of pH. I think you missed the qualification, in italics for emphasis, that this relationship holds at equilibrium and the subsequent analysis of the poster's water to show that it was not at equilibrium.

It is this equilibrium which causes surface waters which are exposed to the air and limestone to migrate toward hardness and alkalinity of 50 each and a pH of about 8.3. This is why tap water that is oversaturated WRT limestone and or CO2 will eventually come to pH 8.3 if allowed to stand exposed to air.

mabrungard said:

One cannot even make that assertion for the mash (which I believe is what AJ is actually referring to) since alkalinity can sneak in there and confound the correlation.

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No, one can't. Water is seldom at equilibrium and mash never so. While we may leave water standing around long enough that it moves towards equilibrium we never do so with mash.

Here's the chart. If you click the following link a pdf with the chemistry/math behind the chart will download: http://wetnewf.org/pdfs/Brewing_articles/Cerevesia/Final_galley

Thanks for the info, everyone! I've barely scratched the surface of water chemistry, so I wasn't sure what to make of this.