brewing with very hard water - reducing bicarbonate

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CraigR

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I live in an area with very hard water, bicarbonate level is about 498ppm.
Other salts make the water fairly similar to burton water

I have had success with darker beers, brown ales porters etc, but never had as much success with pale ales, and am quite new to looking at the water chemistry side of things, (for brewing ales and dark beers, I always understood that hard water is good).

I have tried using bottled spring water as part of the recipe, which lowers bicarbonate, but this still has typical values around the 150 mark, so overall bicarbonate is still 300+

RO or distilled water seems difficult to get hold of in the UK, at least at sensible prices, but would the addition of lactic acid instead do the job for me ? and if so, will the proportion I need to add put my wort pH in the right zone ?

i realise that acid + carbonate will give salt + water + carbon dioxide, so i guess i will be left with a small percentage of lactate salt (in solution ?) which would have no perceptible flavour ?
 
Preboil and decant

A percentage of your Calcium and Bicarbonate will precipitate out of solution. If you know your starting Ca and Bicarbonate values you should be able to determine the values after you boil, there’s an equation you can find online somewhere.

Depending on the values after boiling you could adjust with acid and add more salts if necessary or blend in some RO as well.
 
Good grief, is that from a domestic mains supply? I've never known any public supply that hard. Where in UK are you? Such water would likely have a level of calcium in excess of 150ppm which might be fine for brewing many pale beers, will need large quantities of acid to control alkalinity and lactic acid would leave a noticeable taste.

This is what I mostly use to reduce alkalinity, but have much less of it than yourself.
 
Do you have a way to figure out how much of your hardness is temporary hardness (calcium & magnesium hydrogen bicarbonate)?

Temporary hardness can be removed by pre-boiling your water and letting it cool. These forms of bicarbonate will reform as insoluble carbonate, and you can decant the water off with reduced hardness.
 
If your Ca++ (calcium) ions are at 150 ppm or higher, boiling will reduce your alkalinity to around 65 ppm and bicarbonate to around 80 ppm. That's roughly as low as you can get these two measures of alkalinity via boiling. If your calcium is not at or above 150 ppm, add more calcium ions, then boil.

As to how low you need to get alkalinity (or bicarb.), that is a function of the grist components and their quantities within your recipe. Even 65 ppm alkalinity will likely be too high for lighter colored brews.
 
Ballparking it, each ppm of calcium will complex with and precipitate out 3 ppm of bicarbonate during the boil. This stops working when calcium ions remaining are down to about 12 ppm, and/or (regardless of the residual excess of calcium present) terminates when alkalinity is down to about 65 ppm.

3.0449 ppm of bicarb removed per ppm of calcium for the geeks among us.
 
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Good grief, is that from a domestic mains supply? I've never known any public supply that hard. Where in UK are you? Such water would likely have a level of calcium in excess of 150ppm which might be fine for brewing many pale beers, will need large quantities of acid to control alkalinity and lactic acid would leave a noticeable taste.

This is what I mostly use to reduce alkalinity, but have much less of it than yourself.

in answer to cire, I live near Bury St Edmunds in Suffolk (Home of Greene King) water report gives total hardness as calcium at 163ppm and hardness as carbonate as 408
 
in answer to cire, I live near Bury St Edmunds in Suffolk (Home of Greene King) water report gives total hardness as calcium at 163ppm and hardness as carbonate as 408

Total hardness is a measure of the amount of calcium and magnesium present in water. It is most frequently measured in terms of calcium carbonate, but sometimes as calcium. The latter would be the amount of calcium plus 1.65 times the amount of magnesium. Hence the 408 ppm will be total hardness as calcium carbonate and alkalinity will be part of total hardness and therefore less than 408ppm.

You might care to get your water tested and buy a Salifert kit that measures alkalinity. You should find it is less than you believe.
 
I use the Salifert kits for calcium and total alkalinity (carbonate hardness.) They are easy to use, inexpensive and quite reliable. Available from aquarium supply shops and of course the internet.
 
i may be misinterpreting my water report, here are some numbers (ppm)

total hardness as calcium 163.2
total hardness as calcium carbonate 408

calcium 150
magnesium 8.44

pH 7.38

The calculated total hardness from cire's equation would be = 150 + (8.44 * 1.65) = 163.92 which is pretty close to the report value

If i understand you correctly, the reported total hardness expressed as either calcium or as calcium carbonate is not the true hardness due to calcium, but a value expressed as a calculation incorporating the magnesium.

so in my case, the total alkalinity is around the 370 mark ?

good suggestion on the salifert kit, i'll add one to my shopping list
 
If your bicarbonate is factually listed as being 498 ppm, and your pH is 7.38, then your alkalinity is 408 ppm.

However, your calcium at 150 ppm and magnesium at 8.44 ppm equate to total (or general) hardness at ~410 ppm, because:

Total hardness = (2.4995*Ca++) + (4.11795*Mg++)
Total hardness = (2.4995*150) + (4.11795*8.44)
Total hardness = 409.68 ppm

Since your report of 408 ppm alkalinity and my calculation of 409.68 ppm of "total hardness" are coincidentally so close (with a difference perhaps being only due to rounding errors), could it perhaps be that you are somehow falsely equating a "total hardness" of 408 ppm with "carbonate hardness", and then from there multiplying by 61/50 to arrive at 498 for your bicarbonate ppm?

61/50 * 408 = 498

This approach to computing bicarbonate would be a complete mistake if in fact you are equating total hardness with carbonate hardness, and if this is the source for your derived 498 ppm bicarbonate value, it is not correct (unless by pure coincidence). Total Hardness (also called General Hardness) is not Carbonate Hardness. If this presumption of mine is correct, then in actuality you do not know what your waters alkalinity or bicarbonate ppm values are at all, since you only know its calcium, magnesium, and total hardness values.
 
Here you can find a full water report for your area (I picked an area code at random not knowing where you actually live).

http://waterquality.anglianwater.com/map.aspx?pcode=PE280BE

Looks like you have quite a bit of sulfate (=not so good) but hardly any magnesium at all (=very good).


thanks for the link, this is where I got my water report.

for my particular postcode, sulphate is 86.2 and chloride is 61.3, so a ratio of 1.4, which is moving towards slightly bitter but still balanced
 
If your bicarbonate is factually listed as being 498 ppm, and your pH is 7.38, then your alkalinity is 408 ppm.

However, your calcium at 150 ppm and magnesium at 8.44 ppm equate to total (or general) hardness at ~410 ppm, because:

Total hardness = (2.4995*Ca++) + (4.11795*Mg++)
Total hardness = (2.4995*150) + (4.11795*8.44)
Total hardness = 409.68 ppm

Since your report of 408 ppm alkalinity and my calculation of 409.68 ppm of "total hardness" are coincidentally so close (with a difference perhaps being only due to rounding errors), could it perhaps be that you are somehow falsely equating a "total hardness" of 408 ppm with "carbonate hardness", and then from there multiplying by 61/50 to arrive at 498 for your bicarbonate ppm?

61/50 * 408 = 498

This approach to computing bicarbonate would be a complete mistake if in fact you are equating total hardness with carbonate hardness, and if this is the source for your derived 498 ppm bicarbonate value, it is not correct (unless by pure coincidence). Total Hardness (also called General Hardness) is not Carbonate Hardness. If this presumption of mine is correct, then in actuality you do not know what your waters alkalinity or bicarbonate ppm values are at all, since you only know its calcium, magnesium, and total hardness values.


I think you are right, my total hardness as calcium carbonate is 408, but as outlined in an earlier post, this is due to a calculation if I understand correctly, the reported total hardness expressed as either calcium or as calcium carbonate is not the true hardness due to calcium, but a value expressed as a calculation incorporating the magnesium.

Is there a way I can actually calculate the true bicarbonate levels accurately from my water report ?
 
It appears that the reports from your provider do not give a value for bicarbonate, which is peculiar since it's one of the easiest things to measure. You can calculate an approximate value by summing all the anions and all the cations. You'll then subtract the anions from the cations and you will be left with a value that one can assume is that of bicarbonate. This requires converting all the measurements from mg/l to mval/l and is not trivial and best done with a spreadsheet or similar.
 
oops, my bad,

I just looked at my report again and alkalinity is recorded like so... Alkalinity (as calcium carbonate) as 284ppm

to find bicarbonate, do I just multiply by 1.22 (to get 346.58) ?

thanks to everyone for their input
 
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If your alkalinity is 284 ppm, then boiling it for 20 minutes, settling, and decanting will result in water with a ballpark approximation of 63 ppm Ca++ and 66 ppm alkalinity (~80 ppm bicarb).

284*61/50 = 346.5 ppm bicarbonate
150-(346.5 - 80)/3.05 = 62.6 ppm calcium

1) Edited to correct alkalinity from 248 ppm to 284 ppm.
2) Edited to correct a calculation error.
 
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oops, my bad,

I just looked at my report again and alkalinity is recorded like so... Alkalinity (as calcium carbonate) as 284ppm

to find bicarbonate, do I just multiply by 1.22 (to get 346.58) ?

thanks to everyone for their input

Yes, but someday it may help to know why that works.

HCO3- has a 'rounded' molecular weight of 61 and a valence of -1
CaCO3 has a 'rounded' molecular weight of 100, and its cation and anion components have valences of +2 and -2 respectively.

Normal Weight = Molecular weight/(absolute value of Valence)
Normal Weight of CaCO3 = 100/2 = 50
Normal Weight of HCO3- = 61/1 = 61

61/50 = 1.22
 
Likewise, for the formula:

Total hardness (as CaCO3) = (2.4973*Ca++) + (4.11796*Mg++)

Molecular Weight of CaCO3 = 100.0869
Molecular weight of Ca++ = 40.078
Molecular weight of Mg++ = 24.305

100.0869/40.078 = 2.4973
100.0869/24.305 = 4.11796
 
Bury St Edmonds eh? Maybe you might consider a visit to another local brewery where they might be happy to divulge how they deal with alkalinity.

It seems your main brewery might use that same mains water for brewing, or if not, water that has very similar mineral content. One of their beers when analysed was found to have a calcium content close to 200ppm and chloride in excess of 500ppm which would suggest they use mineral acid to control alkalinity and add calcium salts.
 
oops, my bad,

I just looked at my report again and alkalinity is recorded like so... Alkalinity (as calcium carbonate) as 284ppm

to find bicarbonate, do I just multiply by 1.22 (to get 346.58) ?

thanks to everyone for their input

My water is almost that bad. I've been brewing with it by adding phosphoric acid and/or sauermalz to the mash to adjust the pH to about 5.4 or 5.5, and I used to sparge with RO water but I have switched lately to sparging with cool water instead of hot and not worrying about its pH.

Someday I'm going to try using slaked lime to decarbonate the water. That method should work for your water. You will still need to add a little acid.
 
Bury St Edmonds eh? Maybe you might consider a visit to another local brewery where they might be happy to divulge how they deal with alkalinity.

It seems your main brewery might use that same mains water for brewing, or if not, water that has very similar mineral content. One of their beers when analysed was found to have a calcium content close to 200ppm and chloride in excess of 500ppm which would suggest they use mineral acid to control alkalinity and add calcium salts.

familiar with the other brewery :) and the associated pubs.
 
My water is almost that bad. I've been brewing with it by adding phosphoric acid and/or sauermalz to the mash to adjust the pH to about 5.4 or 5.5, and I used to sparge with RO water but I have switched lately to sparging with cool water instead of hot and not worrying about its pH.

Someday I'm going to try using slaked lime to decarbonate the water. That method should work for your water. You will still need to add a little acid.

is there a 'preferred' method of getting the right pH, ie acidulation over pre-boiling, or is it an individual preference thing ?

i realise adding acid leaves other ions in the mixture, but it seems easier (and possibly cheaper) than pre-boiling the water
 
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