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

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The measurements check out on strange-Steve’s formulae and also my friends. I think I’m going to give it a try at these doses.
 
If this helps anyone, 75% Phosphoric Acid is a bit stronger (mL for mL) than 88% Lactic Acid. At somewhere around 72-73% Phosphoric Acid it becomes pretty close to 88% Lactic Acid (mL for mL).
 
While we're on this subject, having tested my water a few times with a Salifert KH kit, my water is a little softer but still hard at around 250-285ppm CaCO3 (seems it varies a bit over time).....

At the moment I'm adding 5ml lactic acid 80% to 15L tap water in my HLT (I do 10L-ish no-sparge batches so 15L is all the water I'm gonna use in a batch)

In the OP, @strange-steve suggested a max of 0.3mL/L for lactic acid to keep it below the taste threshold, so I'm fractionally over this... but my alkalinity/mash pH is still a tiny bit high at times...

Are there any such taste threshold limitations with either phosphoric acid or CRS?

(I was reading about CRS the other day, in hindsight now it's obvious it would also add both sulphate and chloride which I hadn't realised previously - could be helpful at times, could be a hindrance but noteworthy nevertheless)
 
Apologies, strange-steve. I think I am trying to run before I can walk on this.

Quite possibly, but I won't berate you for it cos I was guilty of the same thing.

My advice for the next few brews would be to simplify what you're doing. You have sufficient calcium already, so all you need to do is reduce the alkalinity and add a little sulphate/chloride like so...

1. Reduce the alkalinity to the appropriate level for the style as per this table:
For a pale beer - 20 ppm
For an amber beer - 35 ppm
For a brown beer - 75 ppm
For a black beer - 120 ppm*

2. For a hoppy beer add 0.2g/l gypsum; for a malty beer add 0.2g/l calcium chloride; for a balanced beer add 0.1g/l of each.

Simple and effective. Don't worry about exact profiles or pH levels just yet. If you follow these steps you'll be in the right area anyway, and it'll be a big improvement over using straight tap water.

* Again, note that these are values for alkalinity as CaCO3, not bicarbonate.
 
Thank you once again. I’m beginning to feel more confident and excited in a geeky sort of way!
 
Given that the Murphy's 75% Phosphoric Acid technical sheet seems to indicate a need for in the neighborhood of twice as much acid addition for any given task as I had computed, I have spent the better part of the day evaluating all of the mash and sparge pH adjustment spreadsheets and online calculators I could gather together to see what they were calculating. They are all in close agreement with my method, and not one of them comes close to agreeing with Murphy's.

pH sticks which are only capable of pH 4.6 at the low end may not reveal how low adding nearly twice as much acid is potentially dropping the pH, since anything below 4.6 will still read as 4.6.
 
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If you are working in HC03, the alkalinity reduction factor is 470 for 75% phosphoric acid.
 
On a mL for mL "equivalency" basis (in the ballpark of a ~pH 5.4 environment), by my figuring:

80% Lactic Acid and 67% Phosphoric Acid appear to be quite close

88% Lactic Acid and 72% Phosphoric Acid appear to be quite close

AMS(CRS) and either 30% phosphoric Acid or 32% Lactic Acid appear to be quite close
 
Given that the Murphy's 75% Phosphoric Acid technical sheet seems to indicate a need for in the neighborhood of twice as much acid addition for any given task as I had computed, I have spent the better part of the day evaluating all of the mash and sparge pH adjustment spreadsheets and online calculators I could gather together to see what they were calculating. They are all in close agreement with my method, and not one of them comes close to agreeing with Murphy's.

pH sticks which are only capable of pH 4.6 at the low end may not reveal how low adding nearly twice as much acid is potentially dropping the pH, since anything below 4.6 will still read as 4.6.
I've heard in the past that the dosages recommended by Murphy's tech sheet for AMS/CRS has been off, so I wouldn't be surprised at this. I've never used it or phosphoric acid so I have no personal experience with them, but I recommend that a test should be done to determine alkalinity reduction by anyone using them.
 
Hi All,

I've used the calculator to try and work out my water profile for a NEIPA. I was thinking of using solely Tesco Ashbeck water. Does this profile look right? Unfortunately I only have gypsum and calcium chloride (no epsom salts). This is for 20l of mash water

TIA
CRS: 0 millilitres Carbonate Reducing Solution - add this to the total water volume!

Gypsum added to mash: 10.3 grams Gypsum (Calcium Sulfate Dihydrate) (Ca SO4 2H2O)
Chalk added to mash: 0 grams Chalk (Calcium Carbonate) (Ca CO3)

Gypsum added to boiler: 0 grams Gypsum (Calcium Sulfate Dihydrate) (Ca SO4 2H2O)
Table Salt added to boiler: 1.07 grams Table Salt (Na Cl)
Epsom Salts added to boiler: 3.55 grams Epsom Salts (Magnesium Sulphate Heptahydrate) (Mg SO4 7H2O)
Calcium Chloride added to boiler: 0.01 grams Calcium Chloride (Dihydrate) (Ca Cl2 2H2O)
 
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OK so let's assume you're brewing an IPA. For this you might want a water profile something like this:

Calcium ~160ppm
Sulphate ~250ppm
Chloride ~50ppm
Alkalinity ~30ppm

This means you want to add roughly 50 calcium, 200 sulphate, 25 chloride, and remove 340 alkalinity. Note these are all approximate, don't be too worried about being a few ppm out, and it's not always possible to get your desired profile.

An addition of 0.35g/l gypsum will add 195 sulphate and 80 calcium.

An addition of 0.05g/l calcium chloride will add 24 chloride and 14 calcium.

An addition of 1.05ml/l of phosphoric acid will remove 340 alkalinity.

Those additions will give the following profile:

Calcium 201ppm
Sulphate 208ppm
Chloride 48ppm
Alkalinity 30ppm

Which actually isn't half bad.


Ok, so I am most likely to have a stab at this tomorrow afternoon.

Before I take the plunge, do you think I should stick to these doses? We've had some toing and froings with calculations and so far, I've come to the conclusion that there really isn't an exact measurement for this level of brewing, but the apps are constrained and quite a way off these measurements.

Based on these, for my session IPA, I am looking at adding for 31 total litres (mash and sparge):

75% phosphoric acid - 32.55 Mls
Gypsum - 10.85g
Calcium Chloride - 1.55g

Or should I play 'safe' and add say half that of Phosphoric? Not a big fan of playing it safe, but I don't want 23l of mineral water!

:)
 
Why not simply do a test of your water first wherein you take 10 Liters of your 367 ppm alkalinity water and add 5.4 mL of your 75% Phosphoric Acid to it, stir well, and see if that brings it down to a measured 5.4 to 5.5 pH with your pH sticks.

If you happen to have a local retail water softener and RO unit sales place that also does retail sales of bottled distilled and/or RO water they will generally quickly tell you the pH of your water by meter (or alternatively perhaps, by adding some chemicals to it and then reading its color on a color comparitor by which to gauge its pH) if you bring them a half Liter or so. They will also gladly tell you the hardness and TDS readings for it. All for no charge.
 
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To make matters more intriguing, I spoke to a pro brewer at a local microbrewery the other day who said, forget trying to get a specific PH and just target the alkalinity you want. The mash will be a good buffer and I would get the beer I want anyway. It’s then just about the right salt additions.
 
He was saying the acid isn’t what really gives you the correct PH, it the combination of acid, salts and malt in the mash.
 
You will want one of these: https://www.amazon.co.uk/API-Freshwater-Aquarium-Water-1-Count/dp/B003SNCHMA

This is what I use to quickly spot test test alkalinity (KH) and total hardness (GH).

KH * 17.848 = ppm alkalinity (as CaCO3)
GH * 17.848 = ppm total hardness (as CaCO3)

Total Hardness (as CaCO3) = 2.49730*(ppm Ca++) + 4.11796*(ppm Mg++)

On average (I.E. approximately, as in a ballpark generalization) roughly 80% of total hardness comes from Ca++ and 20% comes from Mg++

Example for total hardness as CaCO3 = 260 ppm

0.80*260 ~= 2.4973*(Ca++)
Ca++ ~= 83.3 ppm

0.20*260 = 4.11796*(Mg++)
Mg++ ~= 12.6 ppm

But you will still need a means to calculate your acid addition by which to target any give alkalinity, so nothing changes in that regard.
 
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