Water Co. doesn't report HC03.

[ashopis]

Hey there,

The report that my water company gave me does not include HCO3. They do report an alkalinity of 17.

I use brewfather and I'm not sure how much lactic acid to add to achieve a 5.2 pH without knowing the HCO3 levels? I'm thinking it's not estimating my pH correctly without that info. Should I just add HC03 into brewfather until the alkalinity reaches 17? Is there another way I can solve this problem?

Thank you.

 

[Henbrew]

You could try to reach out to them and see if they have data for HCO3. Sometimes they may just not include it on the report.

 

[Silver_Is_Money]

If your waters pH is within what would be considered the nominally 'normal' range, then your waters HCO3- is ~20.7 mg/L (ppm).

Most mash pH prediction assistant software these days uses Alkalinity (as CaCO3), and doesn't require input as HCO3-. The reason for this is that there are three carbonate species, and HCO3- is only one of the three. Alkalinity (as CaCO3) encompasses all three carbonate species.

But if your pH is between ~7 and ~8.3, then pretty close to all Alkalinity will be of the Bicarbonate (HCO3-) species....

 

[VikeMan]

The report that my water company gave me does not include HCO3. They do report an alkalinity of 17.

The alkalinity number on your report should be labeled "as HCO3" or "as CaCO3," or something similar. If whatever software you're using is asking for Alkalinity as HCO3, but your report is reporting it "as CaCO3," multiply the "as CaCO3" number by 1.22 to get the "as HCO3" number.

 

[ashopis]

Hey gang. Thanks for the feedback. Here is the water report that my water company gave me. They said they don't test for Bicarbonate.

In Brewfather, if I leave the HCO3 at zero, the alkalinity comes out as zero as well (see image below). If I boost the HCO3 to 21, the Alkalinity rises to 17 which is what the water company reports. Is that a good way to go about it?

 

[VikeMan]

Looking at your report, it's more than likely that your water company reported Alkalinity "as CaCO3." So, yes, if your software wants "as HCO3," enter 21 (or 20.74, it won't really make much difference).

 

[Silver_Is_Money]

The math behind this is as follows. It involves "Equivalent Weights". When atoms, molecules, and ions react, they react on the basis of weight "equivalence", where weight and molecular charge are both in play whereby to level the reaction playing field across all atoms and molecules and ions (under the highly idealized presumption of full ion dissociation for all reactants).

Calcium has a charge of +2. Ca++
Alkalinity from all sources is "nominalized" to CaCO3, which has a Molecular Weight of 100.0869 grams per Mol.
The "Equivalent Weight" of CaCO3 is thus 100.0869/abs(+2) = 50.04345 grams per EQ

The HCO3- ion has a charge of -1 (which is why it is designated with a single minus sign)
The molecular weight of the HCO3- ion is 61.01684 grams per Mol
The "Equivalent Weight" of HCO3- is 61.01684/abs(-1) = 61.01684 grams per EQ

61.01684 grams of "EQ WT" ÷ 50.04345 grams of "EQ WT" = 1.219277248
(which is commonly rounded to 1.22)

~1.22 is thus the ratio of their respective reaction "weight equivalences".

And lastly 17 ppm Alkalinity (as CaCO3) x 1.22 ~= 20.74 ppm Bicarbonate

 

[Silver_Is_Money]

Here is a chart indicating the nominal "room temperature" prevalence of the three carbonate species at given water pH's:



You can see from this chart that at your pH of 7.3 only about 84% of your Alkalinity is of the HCO3- (Bicarbonate ion) type, so it is not fully precise to presume that 17 ppm Alkalinity = 20.74 ppm Bicarb, but it is generally close enough for our convenience. A bigger problem is that mash reactions typically take place at 148-156 degrees F., and the 'species' chart presented here looks radically different (being highly shifted) at those temperatures. We ignore this inconvenience for our convenience also. We are after all merely ballparking it.

 

[Silver_Is_Money]

When all of the underlying (hidden) software ballparking and presumptions (educated guesses) and convieniences are summed it is amazing as to how many people foolishly and faithfully trust that any software can consistently get their mash pH adjustment advice to within 0.01 pH units, let alone 0.1 pH units. To blindly trust any software to the point of abandoning a pH meter is therefore foolishness. The best that can ever be hoped for is that the multiplicity of underlying educated guesses, ballparking presumptions, and conviences sometimes negate themselves durring summing in a sort of "fuzzy logic" fashion, with the result being a good educated guess as opposed to a bad educated guess. One pH match between software and reality does not mean anything beyond fuzzy logic luck. Which means what happens for one set of circumstances (call it a recipe, combined with procedure and all of the various water and mineral and malt factors) certainly is not assured to happen for all sets of circumstances.

 

[ashopis]

When all of the underlying (hidden) software ballparking and presumptions (educated guesses) and convieniences are summed it is amazing as to how many people foolishly and faithfully trust that any software can consistently get their mash pH adjustment advice to within 0.01 pH units, let alone 0.1 pH units. To blindly trust any software to the point of abandoning a pH meter is therefore foolishness. The best that can ever be hoped for is that the multiplicity of underlying educated guesses, ballparking presumptions, and conviences sometimes negate themselves durring summing in a sort of "fuzzy logic" fashion, with the result being a good educated guess as opposed to a bad educated guess. One pH match between software and reality does not mean anything beyond fuzzy logic luck. Which means what happens for one set of circumstances (call it a recipe, combined with procedure and all of the various water and mineral and malt factors) certainly is not assured to happen for all sets of circumstances.

Thank you for this!!! My brain hurts.

 

[Silver_Is_Money]

Thank you for this!!! My brain hurts.

You've no doubt been told repeatedly to "follow the science", particularly of late. But science is rooted purely in theories, and theories are not required to be rooted or grounded in facts. Theories are merely presumed to model observations, which may themselves be questionable as to whether they are observing facts. And the degree to which they model observation is always questionable and subject to falsification leading to rejection, or to revision, and/or to outright replacement. The error in following the science is in the presumption that science deals in facts.

 

[day_trippr]

Um...that's a rather self-serving narrow definition of science and the practice thereof.

A theory is merely a posit based on conjecture based on some notional trigger(s), and can indeed survive and even flourish in a fact-free environment.

Otoh, a conclusion - if it is valid - is actually a fact-based paradigm...

Cheers!

 

[Silver_Is_Money]

The more I try to fathom facts, the more they appear to be merely probabilities.

 

[ScrewyBrewer]

Don't forget the repetitive experimentation, observation, and critical analysis needed for testing a hypothesis.

 

[DavidWood2115]

I would suggest both @Silver_Is_Money and @day_trippr go (re-)read Karl Popper's definition of science. His falsification principle suggests that for a theory to be considered scientific it must be able to be tested and conceivably proven false. It is only through repeated failure to prove a hypothesis false that we can consider it to be true and therefore elevate it to be called a theory.

So one working hypothesis is that <your favorite brewing software here> predicts pH within 0.1 pH unit. This hypothesis is easily tested on each batch using a (calibrated) pH meter. If after repeated trials you fail to falsify this hypothesis, you may conclude that this is a reasonable theory. HOWEVER, I would recommend that you continue to measure the mash pH as no theory is going to help if you forget your acid addition as I did a few weeks back.

 

[Silver_Is_Money]

Plus or minus any measure of pH deviation from the target hearkens straight back to 'probabilities'.

 

[DavidWood2115]

Plus or minus any measure of pH deviation from the target hearkens straight back to 'probabilities'.

 

[Gnomebrewer]

Science deals in both facts and theories.

In the case here, it's a fact that the pH achieved in brewing most beers is higher than what we target, and that adding acid will lower the pH. The DI mash pH of each individual batch of grain can be worked out factually. Mash pH software use modelling (which aren't really theories) to estimate mash pH.

Not following the science in this case would look something like 'pH doesn't need modifying in brewing. Those who tell you it does are sheep who are spreading lies created by big acid trying to sell more lactic'.

 

[DavidWood2115]

Mash pH software use modelling (which aren't really theories) to estimate mash pH.

At the risk of going too far down the philosophy of science rabbit hole, here is an excerpt from the Wikipedia page on Scientific Theory that I think does a nice job of describing the relationship between models and theories:

Stephen Hawking states, "A theory is a good theory if it satisfies two requirements: It must accurately describe a large class of observations on the basis of a model that contains only a few arbitrary elements, and it must make definite predictions about the results of future observations." He also discusses the "unprovable but falsifiable" nature of theories, which is a necessary consequence of inductive logic, and that "you can disprove a theory by finding even a single observation that disagrees with the predictions of the theory".

I also like statistician George Box's oft-repeated quote that "all models are wrong; some are useful." We all (I hope) know that Newtonian physics is wrong; but most of us never have to deal with general relativity or quantum mechanics to make accurate predictions about our daily lives. I'm sure the mash pH models are all "wrong", but the model I use is useful because it generally predicts within 0.1 pH unit of my measured value.

 

[Silver_Is_Money]

Here's one to ponder.

Most would accept that the angles of a triangle sum to 180 degrees, and that this is indeed a "fact".

But it is only a fact if empty space is perfectly flat, and scientists are still open as to whether or not "empty" space itself is actually flat (albeit that currently most who ponder this are drifting back to the presumption of flat, after decades of prevalently theorizing otherwise). Euclidean Geometry presumes that space is flat, so in Euclidean Geometry triangles angles sum to 180 degrees. But Euclidean Geometry may be incorrect at large scales, and is therefore itself open to falsification.

Many (thanks primarily to Einstein) theorize that wherever there is matter that contains mass the space in its vicinity is not flat, but is warped (whereby we perceive this warpage as gravity). And many now theorize that what we perceive to be "empty space" itself is very likely to be a boiling soup of "virtual particles" that are continually popping into and out of existence within what is generally referred to as a "quantum foam", and is therefore not empty, if this theory has validity.

So it is not a proven fact that the three angles of a triangle sum to 180 degrees. There is only a probability that it does.

 

[ashopis]

My head exploded. I’m getting a pH meter.

 

[DavidWood2115]

Most would accept that the angles of a triangle sum to 180 degrees, and that this is indeed a "fact"

So it is not a proven fact that the three angles of a triangle sum to 180 degrees. There is only a probability that it does.

Sorry, but language matters and this statement is absolutely not a "fact" or a "probability" of being a fact. This is the triangle angle sum theorem of Euclidian geometry (the only geometry most have ever heard of). This is a mathematical theorem proven from a set of axioms or postulates (i.e., assumptions of fact). This theorem relies on Euclid's fifth, or parallel, postulate which states that:
If a line segment intersects two straight lines forming two interior angles on the same side that sum to less than two right angles, then the two lines, if extended indefinitely, meet on that side on which the angles sum to less than two right angles.

If you remove that postulate then you cannot prove that the angles of a triangle sum to 180 degrees. Euclid invented the concept of geometry with his five axioms, but mathematicians have run wild for the past 2,000 years creating new geometries based on alternative sets of axioms. And, just as Newton didn't manage to fully explain the physics of the very large or the very small, Euclid's geometry is a model that doesn't appear to fully explain the space that we live in either. But it is close enough that most of us don't even need to know that there is such a thing as non-Euclidean geometry.