Beginners Guide to Water Treatment (plus links to more advanced water treatment in post #1)

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As I understand it, Calcium in the mash has at least this list of benefits (to which there may be additional benefits):

1) Stabilizes the Alpha Amylase enzyme so it does not get degraded as rapidly at mash temperature.
2) Precipitates malt oxalates in the mash that may lead to downstream haze issues and potentially even bottle gushers (if not precipitated in the mash).
3) Liberates H+ from malt phosphates and thereby lowers mash pH.

One big difference that I see between US and UK home brewing is that in the US we tend to presume that around 50 mg/L of Ca++ ions is generally sufficient in the mash, whereas in the UK the perception (or rather, my perception) is that it may be more like 100-150 mg/L as the desired range for Ca++ ions. That plus we don't have CRS/AMS here, and this is perhaps because (IPA's excluded) we don't typically target as much chloride or sulfate in our beers. And lastly in the USA we generally advise to not add magnesium, or at least to keep it on the very low ppm side, with the perception that the only thing it can contribute is an undesirably nasty/bitter flavor. I doubt if there are any hard and fast rights or wrongs here. Our differences in approach may stem from a more German influence to US brewing. ???
You've made a couple of interesting points there.....

(By the way I've only been brewing about a year, and only very recently started to dabble in water treatment so I am far from an authority on this!)

Up until recently I've been using bottled water (soft, low in all minerals etc) for my brewing. One thing I've generally struggled with is chill haze - my beers that should be clear are cloudy and the ones that should be cloudy are clear!!! :laugh8:

Now recently I changed my process to stop transferring all the crud, sludge, hops, gunk and hot & cold break from the bottom of the kettle to the FV - all in a bid to combat chill haze. However - at the same time I also switched to tap water as I want to reduce plastic waste.

Now it's still a little early to tell, but if I had to choose I'd say my beers are clearer now and I'm getting less chill haze. But one thing I'm not certain of is whether this is due to my process change or is it down to the water (I have very hard water, Alkalinity ~250-280ppm CaCO3 and Ca ~140ppm measured with Salifert test kits)? I had already read something somewhere hinting that Calcium somehow helps reduce chill haze. Who knows.....

Regarding German influence to US brewing - I wonder if some of it is just down to good fortune in that when these folks settled in the US the water profiles they found just happened to be similar to in Germany? By the way, in a recent Basic Brewing Radio episode (October 10, 2019) Maureen Ogle talked a little about how and why these folks arrived in a pro-prohibition US and started brewing - very interesting.....

Regarding CRS - I have a bottle of it, but only used it once so far. I was using lactic acid but after some questionable flavour issues I plan to use CRS from now on. The bottle (or the Brupaks website!) does not say exactly what/how-much hydrochloric/sulphuric acid is in it but the Brewer's Friend Water Calculator lists it as 6.3% HCl / 8.6% H2SO4. Based on this, where I was using 5ml lactic acid 80% to treat 15L tap water, I now need ~17.5ml CRS to treat the same volume - though as I commented recently, once I understood what was in it I now know that CRS also adds chloride and sulphate ions.
 
I found this in the Murphy's technical sheet on AMS (formerly CRS):
35ml of AMS per hl of this water reduces the alkalinity by 64 mg/litre (ppm)

64 mg/L /50.04345 = 1.2789 mEq/L of alkalinity

1.2789 mEq/L x 100 L= 127.89 mEq's of alkalinity

127.89 mEq's / 35 mL = 3.654 mEq/mL for CRS/AMS

Close enough to 3.66 mEq/mL in my book
 
Then I found this in Murphy's technical sheet on 75% Phosphoric Acid:
10ml of Phosphoric Acid per hl of this water reduces the alkalinity by 32 mg/litre (ppm).

32 mg/L /50.04345 = 0.6394 mEq/L of alkalinity

0.6394 mEq/L x 100 L = 63.94 mEq's of alkalinity

63.94 mEq's / 10 mL ~ = 6.4 mEq/mL for 75% Phosphoric Acid

6.4 mEq/mL vs. my presumption that it is closer to 12.1 mEq/mL

This is why I question the validity of this Murphy Technical Data Sheet. One of us is likely wrong here.
 
Ok, well, Murphy's has retested a new sample for me. It is unbelievably different!

PH 6.70
Nitrate 8.40
Total Hardness (as CaC03) 260
Calcium 74.28
Magnesium 11.39
Chloride 84.24
Sulphate 115.26
Alkalinity (as CaC03) 161



Original ones were PH 7.04/nitrate 37.10/hardness 281/calcium 107.17/magnesium 3.2/chloride 24.32/sulphate 13.52/alkalinity 367

For @Argentum : AMS amount for reducing my water alkalinity to 33ppm I am recommended to add 17.26mls into 25l
 
@Argentum

I pro-brewer I have befriended at a local microbrewery has said that he uses 75% Phosphoric Acid and uses this equation:

Actual HC03 - target alkalinity x total water volume/470 (PA reduction factor).

So, in theory for me to reduce my alkalinity to 40ppm for a pale ale:

(196 - 40) x 31 (litres) /470 = 10.2mLs of 75% PA

Very similar to your working out. Between the two, I think I am happy that I'd be in the right ball park.
 
Ah, I just now went back to your water providers Mean/High/Low data and saw there where you stated 216 alkalinity as HCO3 (bicarb), and I totally mistook it as being referenced to CaCO3. 216 mean mg/L (as HCO3-) x 50/61 = 177 mg/L alkalinity (as CaCO3). That agrees well with Murphy's 161 mg/L for alkalinity as CaCO3.
 
Reassuringly close. Phew.

There is one thing I assuredly know about water, and that is that it has to be real. And to be real means definitively that its mEq/L of cations must equal its mEq/L of anions. 99.999% of water profiles that people merely dream up out of the blue will fail this test miserably. But real water always passes this test, and we know that your water is real. With all of the variability in the analysis values garnered for your water from Salifert tests, Murphy's, and your provider, it seems to me that your local water authority has provided the best overall data on a cation/anion mEq balancing basis. I tweaked their mean valuations only slightly to achieve cation/anion balance as can be seen in the thumbnail I've attached below:

Water.png
 
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To show how merely dreaming up an ideal water profile fails miserably, I've conjured one up:

Ca = 100 ppm
Mg = 5 ppm
Na = 15 ppm
Cl = 70 ppm
SO4 = 70 ppm
Alkalinity = 30 ppm

When I checked for cation/anion balance I got the following:
Cation mEq/L = 6.05
Anion mEq/L = 4.03

A miserable failure. Not possibly real. But to me it looks great.
 
You fellas have been so helpful over the last 2-3 weeks. I feel increasingly confident that I am getting my head around the basics.

I don't know if it is a waste of money and I might try a side-by-side comparison one day, but I bought some 5.2ph stabiliser. I think I may brew a batch without it and then brew a batch with it, keeping all the other elements exactly the same. I've heard good and bad things about the stuff.
 
If you look at the phosphoric acid titration curve image I will attach below you will see that from roughly pH 4.0 to pH 5.8 ( I.E., the ballpark that beer and beer brewing plays in, and the region midway between pKa1 and pKa2) there is essentially zero buffering from the phosphate salts that form when phosphoric acid is titrated with a base. This should indicate the buffering value of a commercial phosphate salts based buffer to us home brewers. In the region where we need it most, phosphate salts buffer least, to essentially the extent of nigh-on not at all. The buffering line goes vertical in this pH range, indicating a complete lack of buffering capacity. If it begins to buffer at all it will be (at best case for brewers) at around pH 5.8, but there is little chance for pH 5.2 buffering. The best buffering from salts of phosphoric acid (I.E., phosphate salts) occurs at between roughly pH 6.5 and pH 8.

phosphoric curve.png
 
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You’ve lost me :laugh8:

Is this Targaryen for don’t bother with 5.2ph stabiliser?
 
Buffering capacity can be seen as the measure of the resistance to pH change with the addition of a titrant (in this case it was likely NaOH, a powerful base). It takes only about 0.1 Eq of titrant to move the pH from 4 to 6 on the chart. But it takes about 0.9 Eq's of titrant to move it from pH 6 to pH 8. There is little observed resistance to change in moving a phosphate salt environment from pH 4 to pH 6, and lots of observed resistance to change in going from pH 6 to pH 8. Little resistance to change means little buffering. Lots of resistance to change means lots of buffering. A pH Stabilizer is a buffer.
 
I don't think I've ever seen anyone with any authority on the subject say that 5.2 stabiliser is any good. Most seem to say that it's at best useless and at worst detrimental to the beer.
 
I allways add Ca+Mg to my very soft Scottish water for wine.
It used to be said the best ales in England came from Burton on Trent this was supposed to be on account of the rock hard local water.!!
At least thats the legend.
 
I have my well water analysis, and it's just about as bad as I thought it would be. SO4 is actually 186 ppm. Ward Lab reports only the sulfur, and it must be multiplied by 3X to convert it into SO4. Their SO4-S is shorthand for sulfur derived from SO4....
 

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