Water chemistry inputs (inconsistent reports) - help please!

[JRTurner1234]

Hi there,

I have two sets of water analysis data (which are inconsistent!) and I'm trying to determine which data set I should use (or a combination of the two) for my water inputs.

From what I can tell, the Calcium number on the Murphys report looks wrong.

Given the data in the two reports (attached), what numbers should I put (ppm) against the following ions?

pH
Nitrate
Total Hardness (as CaCO3)
Calcium
Magnesium
Chloride
Sulphate
Alkalinity as CaCO3
Alkalinity as as HCO3
Sodium
Nitrate


Murphys Report:
https://www.dropbox.com/s/k014hg91pm7jxou/Water Report.pdf?dl=0

Affinity Report:
https://www.dropbox.com/s/4oyzobey977lx77/affinity report.pdf?dl=0

Thanks in advance! :)

JRTurner

 

[Grizzly299]

What dates were the water samples taken? Your water profile is not static and so if the samples were tested at different times, there will be variation.

I would go with the most recent.Which I'm going to assume is the Murphy and sons report.

Or you could just go with the mean. Without a report for the water you are using on the day, it's always a bit of a guess.


If you measure your mash pH on the day and adjust accordingly.As well as adjusting your chloride and sulphate ratios to accentuate malt and/or hops.

Your Chloride and sulphate seem to be pretty similar in both reports, in your picture at least. So you'll be in the right ball park with those when you make adjustments.

Your effective hardness is 45.55. leaving you with a residual alkilinity of 280-45.55= 234.45 for the Murphy and sons report.

Or 173.4 for the Affinity report.

So you've still got a lot of alkalinity to overcome either way.


For levels that high you're probably best off using a combination CRS/AMS acid and Acidulated malt to hit the right mash pH .

 

[JRTurner1234]

The issue I had with the Murphy's report was that the cations and anions were way out of balance. However, the anions and cations from the Affinity Water report all balanced...

 

[JRTurner1234]

@Grizzly299

So is this basically a case of mashing and measuring with a ph meter, then adding some acid (in basic terms!)?

 

[Grizzly299]

The issue I had with the Murphy's report was that the cations and anions were way out of balance. However, the anions and cations from the Affinity Water report all balanced...

Consider that it's quite a narrow sighted water report relevant to brewing, so there may be other ions in the water( unreported) that balance it out?

Another possibility is that the two reports give some figures in different units like ppm or mg/l and mEq/l In which case you would need to make everything the same unit in order to make a fair assessment of the balance.

Can't open the reports on my phone unfortunately.


I'm just getting into water treatment, so there may be someone here that has a better answer than me.

 

[Grizzly299]

@Grizzly299

So is this basically a case of mashing and measuring with a ph meter, then adding some acid (in basic terms!)?

That's what I'm proposing. You can calculate as much as you like, but the malts you use can be somewhat unpredictable in terms of their affect on pH and so testing mash pH on the day is the only way to be sure.

 

[IainM]

Your chloride and sulphate are both at the very bottom end of what was sampled in the Affinity report. For Calcium, the Affinity report only has one sample, so doesn't give any indication of the variations. Personally, I'd go with the Murphy one.

 

[JRTurner1234]

Your chloride and sulphate are both at the very bottom end of what was sampled in the Affinity report. For Calcium, the Affinity report only has one sample, so doesn't give any indication of the variations. Personally, I'd go with the Murphy one.

Even though the ions don't balance?

 

[Grizzly299]

Even though the ions don't balance?

I would ignore that.

 

[IainM]

Even though the ions don't balance?

Actually, now I come to look at it, the imbalance is big. The alkalinity is higher than that Affinity report, but the calcium is less than half. Can't be offset by magnesium, because that is specified, so the only other ion that could be there in that sort of quantity is sodium, but it would need 90ppm to balance out. That is a lot less than the 200ppm legal limit, but still quite a bit higher than even high-sodium places like Peterborough, and is more than three time the maximum of the 8 samples in the Affinity report. Hmmm.... ok. I take it back. The Affinity report looks better.

 

[Grizzly299]

@JRTurner1234

Ignore my previous posts, I downloaded the sheets on my laptop and took a closer look.

Looks like the total "Total hardness" figure of 308 (as CaCO3) doesn't add up with the given amounts of calcium and magnesium, on the Murphy and sons report.

Total Hardest as CaCO3 = ((Ca(ppm)/20) +(Mg(ppm)/12.1))*50

Which with the quantities stated in the report gives

((61.47/20)+(2.8/12))*50 = 165.24 As total hardness

Making the assumption that the total hardness and magnesium figures are correct, we can work backwards to get the actual calcium.

(X/20)+(2.8/12.1)*50=308

X + 0.231 *50 = 308

X+ 0.231 = 308/50

X+ 0.231 = 6.16

X = 6.16-0.231

X= 5.929

5.929*20 = 118.58 which is what your calcium figure should be assuming the other two variables are correct.

Using that as your figure for Calcium should balance things out.


Though I may be wrong, it happens frequently.

 

[TartanSpecial]

I think the Murphy's Calcium is too low...the total hardness will have contributions form Calcium (mainly) plus other divalent cations (eg magnesium). If the total hardness is in the Murphys report is 308, the calcium should be approaching 120ish. The affinity Calcium in relation to total hardness looks roughly correct. Your hardness is similar to Espom , and my calcium is around 110. At least both labs come out with similar alkalinities so you should be fairly confident of how much CRS to add. I got a salifert alkalinity and calcium kit(s) so test myself since murphys came out with a too low alkalinity when they tested my water.

edit: I was writing this when grizzly posted... but same conclusion.:thumb:

 

[Grizzly299]

I think the Murphy's Calcium is too low...the total hardness will have contributions form Calcium (mainly) plus other divalent cations (eg magnesium). If the total hardness is in the Murphys report is 308, the calcium should be approaching 120ish. The affinity Calcium in relation to total hardness looks roughly correct. Your hardness is similar to Espom , and my calcium is around 110. At least both labs come out with similar alkalinities so you should be fairly confident of how much CRS to add. I got a salifert alkalinity and calcium kit(s) so test myself since murphys came out with a too low alkalinity when they tested my water.

edit: I was writing this when grizzly posted... but same conclusion.:thumb:

Oh good, glad I wasn't the only one :lol: Perhaps my explanation was a bit more long winded, but I like to show my working out.

Also worth knowing an estimation of the ideal coloured beer for your water. Which is based on the residual alkilinity figure.It basically shows the ideal coloured beer that you can make without pH adjustment. (You will still need to make adjustments to Sulphate and Chloride in order to emphasise characteristics)

Your RA with the Murphy and sons report is 193.64

Making your estimated ideal SRM Range 21.5-26 SRM

So theoretically you can make the following styles without too much tampering( appart from chloride and sulphate)

Porter
Mild
Amber ale
Several Variations of Bock
Strong Scoth ale
Dark American Lager
Brown ale

And a load more.

Again, it's still always worth putting the grain bill into something like brewers friend or Bru'n Water and checking the estimated pH against your mash pH on brewday.

 

[TartanSpecial]

Oh good, glad I wasn't the only one :lol: Perhaps my explanation was a bit more long winded, but I like to show my working out.

The reason it took me so long to finish the post was due to me checking the molecular weight of Calcium. I always remember carbon and oxygen (used to do a lot of organic chemistry) but always forget calcium.

 

[Grizzly299]

The reason it took me so long to finish the post was due to me checking the molecular weight of Calcium. I always remember carbon and oxygen (used to do a lot of organic chemistry) but always forget calcium.

Haha, interesting field to be in and I imagine helps a lot in your understanding of brewing processes.

I've got an electrical engineering background , so chemistry is a bit of a learning curve for me.

But at least it has set me up from a maths point of view! As well as imbuing me with an uncontrollable need to automate everything :lol:

 

[trueblue]

I have heard several reports of Murphy's being unreliable. My only experience with them was after buying sulphuric acid from them. I tested the strength of the acid myself and it was different to the stated strength on the bottle. For a reliable test try Phoenix Analytical http://www.phoenix-analytical.co.uk/ never heard a bad word about them.

 

[JRTurner1234]

@Grizzly299 @IainM @TartanSpecial @trueblue

Thanks for helping me with this! I feel much more comfortable about how to proceed now.

I'm going to have my first attempt at adjusting the water on my next brewday (next Monday), so I'll let you know how it goes!!

:)

JRT