Mash PH issue..

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Mrobson

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I bought a PH reader and have currently used it four times. I’ve been testing my water before every brew and also been using the calculator on this site to see how much CRS to add. Every mash has been between 6.0 & 6.4 fifteen minutes in.

How much more CRS would I need to add per litre to bring the PH down to the recommended level?

Thanks in advance!
 
Also I calibrated the PH reader and test the mash at recommended temperature
 
What @Sadfield said. You can either do this with a salifert kit, or if your water provider supplies it, use the values they give you. I've entered my complete water profile into Brewersfriend and use that for my water calcs. It's a little off, but nothing too bad. I'm guessing some fluctuations in hardness since the water report. I've done a salifert kit, but my water is so alkaline that I need to use the less accurate "half" measures to be able to get a reading. It's not too far off what the water report says though.

Once you know your alkalinity, you can use the table in the link provided above to calculate your additions
 
Thanks for the replys, I’ve been reading that article over and over, very useful and once I got my head around it I took the plunge into water treatment. I test my water before every brew both for calcium and alkalinity, I add the amount of CRS that the calculator in this site recommends but still the PH isn’t where I’d like it to be. Is it just a case of trial and error by adding more CRS or is there a correct amount per litre to lower it by “x” amount of points?
 
To help pinpoint the problem:
What style was your last brew?
What was the alkalinity pre-CRS addition?
What was the calcium ppm?
How much CRS did you add?
What salts did you add, and how much?
 
Thanks for the replys, I’ve been reading that article over and over, very useful and once I got my head around it I took the plunge into water treatment. I test my water before every brew both for calcium and alkalinity, I add the amount of CRS that the calculator in this site recommends but still the PH isn’t where I’d like it to be. Is it just a case of trial and error by adding more CRS or is there a correct amount per litre to lower it by “x” amount of points?

Different grains can affect your PH in the mash, I would be inclined to verify a PH meter with a litmus strip as well until i was sure that it is reading as it should be, the difference between 5.0 and 6.0 on a strip is fairly obvious. Are the sample readings inside the water report min/max from your provider? I would be inclined to try a brew using there data first as a starting point and go from there, bear in mind any filtration will render a water report useless.
 
To help pinpoint the problem:
What style was your last brew?
What was the alkalinity pre-CRS addition?
What was the calcium ppm?
How much CRS did you add?
What salts did you add, and how much?

The last brew was a pale ale.

I tested the water that morning for calcium and alkalinity then used a recent water report from Yorkshire Water.

Ca - 95
Alk - 125.3
Mg - 10.2
Na - 200
SO4 - 250
Cl - 250

Additions according to the calculator off the site were,

CRS - 15.7mm (total water) 28.5 litres
Gypsum - 0.73g (mash) 14 litres
Gypsum - 0.75g (boil) 14.5 litres
Epsom - 2.83g (boil)
Calcium Chloride -1.31g (boil)

A PH of 6.4 fifteen minutes into the mash.

Cheers
 
Last edited:
Different grains can affect your PH in the mash, I would be inclined to verify a PH meter with a litmus strip as well until i was sure that it is reading as it should be, the difference between 5.0 and 6.0 on a strip is fairly obvious. Are the sample readings inside the water report min/max from your provider? I would be inclined to try a brew using there data first as a starting point and go from there, bear in mind any filtration will render a water report useless.


I’ve just ordered some test strips to see if it is the meter at fault.
 
That's a rather unfortunate water profile you've got there. Sometimes you can't add your way to a good profile, and that's probably the case for you.

Taking what you've said above, your post-treatment profile looks something like this:
Alkalinity 20
Calcium 130
Sulphate 400
Chloride 320
Magnesium 25
Sodium 200

That's really minerally, even for British styles, especially the sodium which should generally be <100 ppm.

I would suggest trying to dilute your tap water with RO if you can get it, or if not Tesco Ashbeck. A 50/50 blend will give you a better starting point, or better yet 75/25 RO to tap.

The next thing I'd suggest is getting rid of the epsom salt addition. You have enough magnesium already and it adds a load of sulphate which you definitely don't need.

Just for instance, for a pale ale I would usually aim for something like this:
Alkalinity 20
Calcium 100
Sulphate 200
Chloride 50
Magnesium 5-10
Sodium <25

But anyway, that doesn't really answer the question of why the mash pH is so high. It does seem unusual, the calcium and alkalinity look pretty good for a pale ale. Even with a 100% pale malt grist I wouldn't expect much higher than 5.7 or so. Try your next brew with the RO or bottled water as suggested, and see what the pH is like. I would also confirm the strength of your CRS by doing a small test: take 2L of tap water in a jug, test alkalinity, add 1ml of CRS, give a good stir, retest alkalinity. It should have dropped by about 95ppm.
 
That's a rather unfortunate water profile you've got there. Sometimes you can't add your way to a good profile, and that's probably the case for you.

Taking what you've said above, your post-treatment profile looks something like this:
Alkalinity 20
Calcium 130
Sulphate 400
Chloride 320
Magnesium 25
Sodium 200

That's really minerally, even for British styles, especially the sodium which should generally be <100 ppm.

I would suggest trying to dilute your tap water with RO if you can get it, or if not Tesco Ashbeck. A 50/50 blend will give you a better starting point, or better yet 75/25 RO to tap.

The next thing I'd suggest is getting rid of the epsom salt addition. You have enough magnesium already and it adds a load of sulphate which you definitely don't need.

Just for instance, for a pale ale I would usually aim for something like this:
Alkalinity 20
Calcium 100
Sulphate 200
Chloride 50
Magnesium 5-10
Sodium <25

But anyway, that doesn't really answer the question of why the mash pH is so high. It does seem unusual, the calcium and alkalinity look pretty good for a pale ale. Even with a 100% pale malt grist I wouldn't expect much higher than 5.7 or so. Try your next brew with the RO or bottled water as suggested, and see what the pH is like. I would also confirm the strength of your CRS by doing a small test: take 2L of tap water in a jug, test alkalinity, add 1ml of CRS, give a good stir, retest alkalinity. It should have dropped by about 95ppm.

I feel stupid!

Just looked on the Yorkshire Water website again to check the report, turns out I’ve been looking at the wrong figures. Whoops!! No wonder you mentioned my water being so bad.

After reading the report properly (using the mean figures) and using the figures from my test samples I’ve got this,

Ca - 95
Mg - 24.2
Na - 18.71
SO4 - 102.175
Cl - 34.475
CaCO3 - 125.3

Would this now explain the PH being so far out?
 
Using the proper report and the same volumes of water as my last brew has given these additions.
 

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This is an odd one. Your CRS additions appear to be correct and you have enough calcium in your water that I would say a CRS addition on it's own would be enough. A long shot, what is your setup and is there any lime scale/beer stone build up in your equipment? And to clear any doubt, you are adding the CRS to your water first and not to the mash with the salts?
 
The CRS gets added to all my water before I measure out the mash volume.

I mash in a cool box and use a stove top pan to boil wort and heat my water in. There is no build up in either the mash tun or the boil pan.

Cheers
 
I would suggest trying to dilute your tap water with RO if you can get it, or if not Tesco Ashbeck. A 50/50 blend will give you a better starting point, or better yet 75/25 RO to tap.

My tap water profile is not as bad as yours, but mine is problematic for brewing most beer types and seems to change seasonally. When I decided to simplify my brew water method, my beer got much better.

I make up 35L of brew water the day before... For a pale ale type beer, with no roast malts I use 25L Ashbeck and 10L tap water. I give the tap water a 10 minute boil to reduce temporary hardness before mixing with the Ashbeck water. Then I adjust down the PH of the brew water to 5.8 with phosphoric acid.

At the other end of the scale, for example a Stout with shedloads of roast malts, I'd use 10L Askeck and 25L tap water and adjust PH to 6.2.

I tend to use a sliding scale with most beer brewing... Paler beer, less coloured malts, more Ashbeck, less PH. Darker beer, more coloured malts, less Ashbeck, more PH.

The way I use this dilution method probably isn't the best way, but it works for me, with my tap water and I can make good beer too!

Back to OP... Do you use a buffer solution to check your PH meter is reading correctly? (all readings should be taken @ 20c)
 
Would this now explain the PH being so far out?
Not really, because the two main contributers to mash pH (ie alkalinity and calcium) are still the same. This is an odd one alright. Firstly I would check the strength of your CRS as described above, just to make sure it's doing what it should be doing.
 
My tap water profile is not as bad as yours, but mine is problematic for brewing most beer types and seems to change seasonally. When I decided to simplify my brew water method, my beer got much better.

I make up 35L of brew water the day before... For a pale ale type beer, with no roast malts I use 25L Ashbeck and 10L tap water. I give the tap water a 10 minute boil to reduce temporary hardness before mixing with the Ashbeck water. Then I adjust down the PH of the brew water to 5.8 with phosphoric acid.

At the other end of the scale, for example a Stout with shedloads of roast malts, I'd use 10L Askeck and 25L tap water and adjust PH to 6.2.

I tend to use a sliding scale with most beer brewing... Paler beer, less coloured malts, more Ashbeck, less PH. Darker beer, more coloured malts, less Ashbeck, more PH.

The way I use this dilution method probably isn't the best way, but it works for me, with my tap water and I can make good beer too!

Back to OP... Do you use a buffer solution to check your PH meter is reading correctly? (all readings should be taken @ 20c)

I used to buffer solution that came with the reader and calibrated it at 20c and have tested the mash PH after bringing the temperature down to 20c.

The strips I’ve ordered should be hear in the next day or two so I can test if it’s the reader itself that’s causing the confusion.
 
Not really, because the two main contributers to mash pH (ie alkalinity and calcium) are still the same. This is an odd one alright. Firstly I would check the strength of your CRS as described above, just to make sure it's doing what it should be doing.

Just done the CRS test,

Starting Alk - 130.7
After 1ml of CRS - 44.8

That’s 85.9 difference, a little off the 95 you mentioned.

So, should I now be adding 10% more CRS than the calculator is telling me to make up the difference?
 
You need watta like mine. Did an ESB yesterday - pH settled at 5.2 dead, no fiddling with chemicals. I know that doesn't help but I can't contain my smugness.
 
Why don’t you send a sample of your water off for analysis, it’s not expensive and takes out all the guess work. I did mine as the sheet shows and they even tell you what to add for different beer styles. The sheet shown is for bitters and IPA’s Brew UK now deal with the water treatment and not Murphys who I used. Brew UK send the water to Murphys.
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