Consistent Low mash pH with dark beers

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The pH of my water is 5.8. We have some green staining on our shower units.
Off subject a bit but you should consider getting a water treatment system to raise the pH of your household water. The green stains are likely your copper pipes dissolving. Low pH water will do that. Replacing the pipes is an expensive repair, not to mention the potential damage repairs when one starts leaking.

I saw this from time to time in my inspection career. Some of the wells in my area produce acidic water. You can’t tell how much damage has been done to the pipes without cutting out a piece and measuring the thickness.
 
Thanks @InspectorJon and @day_trippr; that fills in some of my missing "trans-Atlantic" knowledge. I wasn't appreciating that many (all?) of your water companies are confident enough of their own infrastructure to deliver acidic water direct to the households in their care, and don't give a fig for the infrastructure in the houses they are supplying. I think I've figured correctly that "RO" treated water (which is acidic as-is) are used quite a lot over there.

Whereas: Over here the water companies (mostly, if not all, in foreign ownership) don't give a fig for the infrastructure of the houses they supply either! But legal requirements (ineffective and which they'd happily ignore) and an inherited aging infrastructure (which costs them money and can't entirely ignore) forces them to "dose" acidic water (with slaked lime). The only "RO" treatments are mainly for desalination of some remote coastal and small island communities. Acidic waters are confined mainly to Scotland, North and Western fringes of England, and Wales (about 5% of the population). It would be very rare to see tap water supplies dip below pH7 (I think they are allowed to supply down to pH6.5).


This explains why I get limited response to my queries about remineralisation of "RO" and acidic tap waters. Erm ... ignoring lack of response 'cos most find me incomprehensible anyway!

All domestic "RO" units appear to remineralise over here (some commercial units, like the supplier "Spotless", supplier to window cleaners mostly, do not remineralise). Remineralisation of "RO" water is usually achieved with Calcite block, which I think is the same over there?
 
This is only adjacent to the topic but it might help people following along. My actual measured pH was pretty consistently coming in lower than Brewfather was predicting when the batch called for lactic acid additions. I first rationalized that my source of 88% lactic wasn't diluting the strength properly. The two things I was actually screwing up.

1. Sample measurement error: The graduated mini beaker I was using to collect my wort sample was also the same container I was mixing my salts and acid in. I'd measure the salts, fill it with some warm strike water and then dose in the lactic and stir it all up. Then I'd just dump it in and rinse it real quick. I'm quite sure some residual acid stayed in there and was acidifying my sample just enough.

2. Actual Overdosing Acid: I measure my lactic by sucking it out of the container with a syringe equipped with a 4" blunt needle. I'd fill it to whatever, 4mL. I knew it would hold extra acid in the needle, but it would be stuck there so no overdose. Yeah, except after realizing that leaving acid in the needle would rust it, I'd suck strike water in to the syringe and squirt it back INTO THE KETTLE. :agressive:
 
I wasn't appreciating that many (all?) of your water companies are confident enough of their own infrastructure to deliver acidic water direct to the households in their care, and don't give a fig for the infrastructure in the houses they are supplying.

I don’t think public water utilities in the US supply acidic water. They are pretty highly regulated. There are a lot of private wells and other private water sources that can produce acidic water.
 
Then we have the often ridiculed:

5.2 pH Stabilizer.

Used in the mash, it will dissociate excess hydrogen ions to a pKa of ~5.3 - 5.4.

No matter the "error" that's causing your low mash pH, this will buffer your mash so it doesn't go below ~5.4-5.7 pH.

Only to a certain extent though as it will only buffer away so much acid... at the expense of adding sodium ions (those released from their phosphate bonds in the acid reaction) and residual sodium phosphates (those that are not consumed by excess acid).

Don't think it will work with phosphoric acid but lactic, sulfuric and hydrochloric should be ok.

5.2 pH Stabilizer will buffer excess acid so the mash pH doesn't get too low (when adding acid to a high pH mash). It will also raise the mash pH by neutralizing excess acid (when added to a low pH mash). Lower or higher than pH 5.2.

Kinda like the lazy mans mash pH adjustment. Just add some 5.2 and some acid, no measuring required! The 5.2 will mop up any excess acid!

In practice it's best to understand and calculate your mash chemistry but a buffer such as 5.2 could prove useful in situations like this.
 
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Off subject a bit but you should consider getting a water treatment system to raise the pH of your household water. The green stains are likely your copper pipes dissolving. Low pH water will do that. Replacing the pipes is an expensive repair, not to mention the potential damage repairs when one starts leaking.

I saw this from time to time in my inspection career. Some of the wells in my area produce acidic water. You can’t tell how much damage has been done to the pipes without cutting out a piece and measuring the thickness.
I was going to get a neutralizer 24 years ago when we built the house but the plumber talked me out of it. We have wirsbo plumping throughout the house...no copper. Back then he said you are going to spend 1500 now to save some faucets that might fail 20 years from now....by the time they fail you might want to upgrade anyway.
 
No copper, yet green stains.

Often ridiculed because it doesn't work. and it doesn't work because it can't work.
The green stains are from the copper in the fixtures and a little copper around the pressure tank....everywhere else wirsbo.
 
[EDIT: This post has been updated considering further information!]

I thought I'd dig a bit deeper to see if I could uncover something (it's all related to a project I'm on, so I don't mind).

Into my copy of Bru'n Water goes the water detail and grain bill for the recent brew of this thread (post #18).

My own water spreadsheet calculates alkalinity (shown in this thread "as HCO3"). Because it's calculated the water has to balance, and to get the HCO3 about 3, it needed a bit of padding out. There's always nitrate (often agricultural pollution) so I used that. 25mg/L, which is a bit high and a bit out of character with rest of the report but not at all unusual from an area of fairly modest intensity of agriculture (half the legal defined limit - 50mg/L -in the UK). The results are plugged into Bru'n Water:

1734372003610.png


"My spreadsheet" by-the-way is the, widely despised (I don't know why so many dislike it so much!), "Defuddler" linked in my forum signature below (blimey, I should charge for it!). It balances perfectly ... because it has to! (the "0.00" is what you're looking for).

1734373306551.png


The grain bill is plugged in, and the water details into the water adjustment page, and:

1734442584126.png


Ignore the red boxes, Martin is a little "draconian" with his "warnings"!

But the interesting box in that illustration is the "Estimated Mash pH". People in this thread do say ignore the attempts at predicting pH ... and it's true, it is virtually impossible to align the pH with a lot of physical measurements and NO actual data concerning the very changeable acidity of the grains involved (the product of "natural forces" which folk do attempt to provide a value for - e.g. the very empirical "pH-DI" shenanigans). But as long as you know it's only "roughly", it's worth having a stab at it.


"Expected Mash pH" is 5.64. I think that's pretty close to @Hartwa's conclusion?
 
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I downloaded a new copy and still get 5.67 if I remove the chalk addition.

My ions balance without doing anything extra...whereas your attempt did not???

I am using 1.7 for the 2 row
60 for the crystal
65 for the brown
350 for the chocolate.

The chocolate is the only one I am treating as roasted. I get real close if the brown is selected as roasted....is that what you did?
 
I was going to get a neutralizer 24 years ago when we built the house but the plumber talked me out of it. We have wirsbo plumping throughout the house...no copper. Back then he said you are going to spend 1500 now to save some faucets that might fail 20 years from now....by the time they fail you might want to upgrade anyway.
PEX (Wirsbo) is a good solution to acidic water, especially if used proactively like you did.
 
I downloaded a new copy and still get 5.67 if I remove the chalk addition.

My ions balance without doing anything extra...whereas your attempt did not???

I am using 1.7 for the 2 row
60 for the crystal
65 for the brown
350 for the chocolate.

The chocolate is the only one I am treating as roasted. I get real close if the brown is selected as roasted....is that what you did?
My water assessment can only be "balanced" because I calculate alkalinity based on add everything up, and what's missing is the alkalinity. This is a normal way of working alkalinity out, but most homebrewers (on all the forums I've been on) won't use it for some reason that no-one knows (I do try to get an answer!). It uses this formula Total Alkalinity = ∑conservative-cations - ∑conservative-anions where "conservative" means "not alkalinity". So "Total Alkalinity" is all the "alkalinity" anions (usually carbonate and bicarbonate, but in drinking water can include silicates, phosphates, and even hydroxide (such as Lime, commonly used to raise the pH of acid waters). Alkalinity - (Wikipedia). I required 25mg/L of Nitrates to get Alkalinity down to 3mg/L as you had it documented, which is a good bit more than I'd prefer.

1734443756139.png


Thanks for the grain colour data. Martin's Web site (https://www.brunwater.com/water-knowledge) appears to be a bit more up to date than the documentation in the spreadsheet, But the colour information doesn't help with your issue: It jumps from "Base Malt" at up to 20L to "Roast Malt" at over 200L ... Your "Brown Malt" at 65L doesn't get a look in. I continue considering "Roast Malt" as starting above "Base Malt" i.e. 20L upwards. For the sake of acidity calculations, the colour is truncated anyway (at about 165L? There's a techie reason for it) but all this grain colour/acidity business really needs some input from @mabrungard.

Annoyingly I've overwritten the Bru'n Water settings I was using yesterday, and my attempts to rebuild it isn't working. Perhaps it's a good thing? If I can't get it back as it does seem I had an error in it! I'll update the original post ... you'll like it, it complies with what you're saying now!
 
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{EDIT: Batch volume corrected to match example. Aesthetic change but does change the gypsum and CaCl2 to match new volume.]

I said I'd do this for @mashdar because my previous example was a bit lame.

I'm still finding pH 4.7 hard to comprehend.
Okay, using the illustration I prepared for @Hartwa, but chucking out the chalk and cutting back on the slaked Lime to get a mash about pH5.3:

1734520839033.png

I wanted to bump up the Calcium levels, along with the Chloride and Sulphate levels. I'm using Chris Colby's practise of a teaspoon of gypsum and a teaspoon of calcium chloride flakes. I know those salts will play havoc with the mash, so I hold back the salts to put in the boiler or sparge. Bru'n Water has an option for this "Add Hardness Minerals to Kettle". The value turn orange to indicate what'll happen.

Now watch what happens to the pH if I put them in the Mash Tun instead. Believe me, this does happen, and I'd been trying to figure it out for ages:

1734521602614.png
 
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I downloaded a new copy and still get 5.67 if I remove the chalk addition.

My ions balance without doing anything extra...whereas your attempt did not???

I am using 1.7 for the 2 row
60 for the crystal
65 for the brown
350 for the chocolate.

The chocolate is the only one I am treating as roasted. I get real close if the brown is selected as roasted....is that what you did?

I know I mentioned it in #30 but I'll mention it again.

If you post screenshots of your Bru N Water tabs, it would help us to help you figure out your problem.

Brown is and would be treated as a roast malt in Bru N Water (hover over the red triangle in the upper right corner of the cells to view the help text).

1734450777133.png
 
This is the 1 I got 5.3 ph on in actual vs. 5.5 predicted if I use roasted for the brown. But it turns the cell red so it thinks it is wrong. See attached
 

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Bru N Water predicts 4.88 after I enter your information for your small batch (without any correction)

You need 0.75 grams of lime to correct the pH to 5.4

I don't see any thing wrong, except that you need to quit using chalk.


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You need 0.75 grams of lime to correct the pH to 5.4:


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... But it turns the cell red so it thinks it is wrong. ...
You have to be careful with that. @mabrungard's use of color to indicate "errors" is a little bit buggy, especially at the edges of Bru'n Water's performance envelope. Look at my articles above (e.g. #55). I'm obviously ignoring them!

For example: In that #55 post those Bicarbonate entries are all red to warn I'm using Bicarbonate and acids together ... I'm not using acid (including "acidulated malt") at all! Using those "Add Hardness Minerals to Kettle" and "Add Sparging Water Mineral Additions to the Mash" are particularly good at triggering the bugs. Those red "Additions" boxes have a note to say, "It is OK to ignore the warning ...", in which case shouldn't they be Amber, not Red?

I suppose I'm happy to ignore the warnings and errors 'cos I'm British and there was a little friction 'tween Martin and some British brewers in the distant past ... the British like lots of mineral in their brewing water, the rest of the world do not (apparently). Doesn't bother me much, so I'm okay ignoring them ... and @mabrungard, you'd say ... ?
 
I hadn't updated the "batch volume" on that post #55 earlier. It doesn't make any difference (solely aesthetic, apart from changing the "hardness minerals" to match), but it's nice to have it all say the right things.

The "batch volume" (and therefore "sparge volume") remains uncorrected in post #51 because the allowed correction time has elapsed. But again, it doesn't actually alter the parts being discussed (and there are no "hardness minerals). Just be aware if trying to dig deeper in that diagram! The final result will be some very weak beer 😝
 
What is your equipment like? Does your mash tun have a lot of dead space where water is not mixing with the malts?
 
... My ions balance without doing anything extra...whereas your attempt did not??? ...
Ah! ... Have you been telling whoppers? One of those screenshots you posted above had lots of "extras". Like 20mg/L of Nitrates (I was guessing 25mg/L).

Not that I mind; I like the puzzles it creates (I have to exercise this accidentally broken head of mine, else it just stops!). I updated the information you had already given me but had to push the Nitrates up to 31.4mg/L to keep the balance (some of the "extras" you listed sit on the opposite side of the equation, like 4mg/L Potassium).

It all helps me update my painting of a picture of where you live: A well, so not too populous. A shallow well, with fairly small catchment for rain, so hasn't much chance to dissolve a lot in the water. And a good bit of (fairly intensive) agriculture in the surroundings (the source of much of that relatively high Nitrate level ... but I'm not mentioning the "Po..." word!). And ... I can still be completely wrong! No-one will care!
 
Lol...my well is 120' deep. It is agriculture....

The other question about my mash tun...it has hardly no dead space.

In any case...i got this figured out. My pickling lime has turned to chalk. It does not go into solution at all. I did not know it could turn...it is probably 10 years old. When you consider my pickling line additions are not being made my ph matches pretty closely.

If I get some time I might try a test batch with some new lime.
 
Lol...my well is 120' deep. ...
I'll need to adjust my idea of "shallow/deep". I thought your 120' sounded "borderline" so looked it up: Turns out I exaggerate "deep" and 120' is quite a bit more than just "deep"! Ah well, 'tis deep then. I guess I'm not a reliable judge of "wells" (I've only seen them in GB castles ... and one Spanish one 10' deep!).

Good you're getting it sorted! (... Now, I wonder how old my Lime is? ...).
 
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