Graham's water calculator "Guessing" chloride and sulphate

[DerbyshireNick]

Background: my current supply is mixed water source and alkalinity testing so far has shown it swings around to a limited degree. With this in mind I have ruled out official water testing as there just isn't any point as the results will be outdated.

Ive been on a bit of a research and learning mission of late and have found the below nomograph invaluable (visual thinker) in understanding how the various components of water play into mash PH.



With the above in mind I was happy, as I can, with salifert kits test for Calcium, Magnesium and Alkalinity on a brew-by-brew basis. While this doesn't cover everything needed for Grahams calculator it at least allows me to understand what is going on and how I get to my RA.

The problem I have is that putting in figures from my water reports leads to a totally unbalanced Cations/Anions ratio. Given an alkalinity of 108ppm and a water report Calcium value of 85ppm I became increasingly suspicious given the rule of thumb that says calcium is around 40% of the value of alkalinity, where as this is nearly 90%.

So, the question: If I supply totally accurate (as accurate as the test and my humanity) values for Alkalinity, Calcium and Magnesium and then take Sodium, Chloride and Sulphate from my water report things don't quite stack up with said Cations/Anions ratio. If I scale the chloride and sulphate up I can achieve a balance and the net result on the advised additions isnt sillyily differed (0.5g different to Calcium Sulphate/Chloride over the entire mash addition based on 14L). Does this sound like a sensible approach. If I have understood my experimentations with various calculators and the nomograph it is the alkalinity, calcium and magnesium that mostly play into the mash ph and thus those are the most critical in the first instance. The levels of added calcium chloride and sulphate changing marginally due to educated guess work will only really have an effect on the taste profile, and due to the changes being quite small I dont think this will even occur?

Possibly over thinking this...

[Aleman]

I'm going to point out that that Nomograph is based on Kohlbachs work on residual alkalinity at the back end of the 1950's. From what I have been able to determine his work was based on thin mashes using low mineral content liquors, and continental malts. There is no follow up evidence or work to suggest that his findings work with a thicker mash, liquors with a mineral content typically used by British breweries, and UK malts.

With that in mind I take that nomograph with a pinch of salt.

I also take with a pinch of salt the published profiles for beer styles.

As I've said in the past, if you don't know what you have in your starting liquor, then randomly guessing values, and throwing treatment salts at is is not water treatment, it is more akin to witchcraft.

Don't over think or over complicate water treatment, there really is little point.

1) reduce chlorine with metabisulphite
2) adjust alkalinity to rough levels required by the beer style and grist you are using . . . Again you don't need a complex spreadsheet and malt analyses to do this . . . Pale beers with low levels of crystal malts aim for 30-50mg/l, as the beer colour darkens and the crystal content increases then adjust the alkalinity up to about 125-150
3) If required . . . and it may not be if your water already contains a reasonable level, adjust calcium to a minimum of 100 mg/l using gypsum if you want to emphasise hoppiness/dryness and calcium chloride if you want to emphasise malt/body/fullness. If you want to sway the flavour ions without adding calcium, and you have a high alkalinity then use sulphuric and hydrochloric acids to adjust alkalinity.

I only measure alkalinity and calcium every time I brew and my water changes sometimes dramatically

Code: Select all

              2015                          2014
              26th Mar  21st Feb  21st Jan  22nd Nov  28th Oct  11th Feb 
Calcium    -    17.8      20.6     14.8       30.8      35.7      24.3
Magnesium  -     3.0       3.3      2.1        6.9       8.3       3.1
Sodium     -    11.3      12.0      8.2       15.4      16.2      12.0  
Potassium  -     0.7       0.9     <0.5        0.6       1.0       0.7

Sulphate   -    33.3      37.3     27.4       50.6      68.2      42.8
Chloride   -    12.0      11.3      8.5       11.7      15.6      11.1
Phosphate  -     6.1       6.8      5.9        6.2       6.2       4.7
Nitrate    -     1.9       1.7      1.3        1.7       2.1       1.3

Alkalinity -    30.0      33.0     18.0       67.0      67.0      32.0  

Alkalinity has been measured at 135mg/l . . . with a similar rise in calcium sulphate and chloride. While getting a single measurement of your water profile may seem to have little point, when you get several as time goes on, you can start to derive much more meaningful guestimates as to what your water contains at any point in time. If you wish to proceed beyond ' basic water treatment of boil, to reduce alkalinity and add a tsp of gypsum in the mash and one in the boil (Which for a number of water in the UK is pretty blooming valid) then you have to bite the bullet and get a series of profiles.

[DerbyshireNick]

I think we are actually on the same page here Aleman.

My muddled point being that knowing my Calcium, Alkalinity and Magnesium (I have the tests so why not) I can get the mash ph in the ballpark and that is, at this stage what matters to me. I am far more interested in removing the current off flavours caused by moderate alkalinity (108ppm) in pales which is causing husky flavours (mash ph 6 - 6.2) and an over all bland beer.

So the question was, which I guess you have answered is ... go with the water report values for sodium/chloride/sulphate which makes an "impossible" water or raise them up a bit to get a mathematically correct water which in my gut, is most likely more accurate than the water report but obviously as you say, both are guesses. But... they key being that changing them doesn't change the required CRS so... essentially I can go with the water report, I can go with my educated guesses or we can do with the teaspoon. All are equally guesses.

Side note: The reason I am all over this is my old house had soft water with an alkalinity of 20 mg/l and <10mg/1 of everything else of note. I am now on quite a different water which is reasonably mineral rich but with a higher alkalinity. I had previously just ignored alkalinity as a topic because I just didn't need to go there. Although I now understand why the one stout I ever made on it wasnt the best

Cheers as ever Aleman, Ill get my CRS sorted and not get too stressed about the salts.

[Aleman]

The thing with sulphate and chloride, is that yours might be the opposite to mine, chloride > sulphate or it could eb the other way round, and you can create 'valid' balanced profiles either way round.

About all I do, is to adjust alkalinity to get the mash pH right, then add 100mg/l Calcium using sulphate or chloride as I want depending on the taste I want to bias.

Then again, as my water has pretty low levels I can achieve significant results with low levels of changes.

[DerbyshireNick]

according to the water report its 28.6 mg/l of each (ive ignored the .012 difference)

Ill report back in a month or so, hopefully get to brew a pale this weekend. Ill know by the end of primary if its solved the issues.

Cheers for the feedback.

[Jocky]

Don't over think or over complicate water treatment, there really is little point.

1) reduce chlorine with metabisulphite
2) adjust alkalinity to rough levels required by the beer style and grist you are using . . . Again you don't need a complex spreadsheet and malt analyses to do this . . . Pale beers with low levels of crystal malts aim for 30-50mg/l, as the beer colour darkens and the crystal content increases then adjust the alkalinity up to about 125-150
3) If required . . . and it may not be if your water already contains a reasonable level, adjust calcium to a minimum of 100 mg/l using gypsum if you want to emphasise hoppiness/dryness and calcium chloride if you want to emphasise malt/body/fullness. If you want to sway the flavour ions without adding calcium, and you have a high alkalinity then use sulphuric and hydrochloric acids to adjust alkalinity.

I only measure alkalinity and calcium every time I brew and my water changes sometimes dramatically

Good process.

As I've mentioned elsewhere, I have found Graham's water calculator very valuable in understanding water chemistry.

[DerbyshireNick]

Indeed, ive since been on a bit of a knowledge voyage and from all my reading and experimenting with Grahams calculator I came to the conclusion too that as long as you get the alkalinity and calcium right everything else can fade away.

Its only alkalinity and calcium that really change the additions. I ignore magnesium and salt additions. All I am interested in is CRS, Calcium Chl/Sul depending on the style.