How accurate are ph indicator strips?

(That's water to the rest of us!) Beer is about 95% water, so if you want to discuss water treatment, filtering etc this is the place to do it!
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Dennis King
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Re: How accurate are ph indicator strips?

Post by Dennis King » Sun Oct 25, 2020 10:38 am

Top Cat wrote:
Sat Oct 24, 2020 5:39 pm
Top Cat wrote:
Fri Oct 16, 2020 7:33 pm
Eric wrote:
Thu Oct 15, 2020 10:39 pm


A very good step. Please post the findings of the analysis to open this discusion further.
Will do, as I’ll need help to use the results!!!
Hi guys.
Please find results of water analysis below

Sodium as Na, mg/L 32.0
Potassium as K, mg/L 4.0
Magnesium as Mg, mg/L 7.8
Calcium as Ca, mg/L 51.8
Chloride as Cl, mg/L 51.9
Nitrate as NO3, mg/L 16.4
Phosphate as PO4, mg/L 4.5
Sulphate as SO4, mg/L 34.6
Total alkalinity as CaCO3, mg/L 92
pH 7.22
Conductivity uScm-1@20c 411

For my next brew I intend to try Dennis Kings Galaxy Delight, a strong well hopped pale ale, that uses malts and yeast I’ve never tried before.
I’d like to ask for your help on adjusting 36 ltrs of water for this particular beer.
Another question I’d like to ask although I suppose it should be on a separate topic, is the recipe requires dry leaf hopping 40 grams. Anyone know roughly how much weight I need to just get the hop bag to submerge? I usually use pellets and let them fall to the bottom of the fermentation vessel.
With a little luck Dennis might read this post!!!
TC - To be honest I don't always dry hop with this recipe and the last few times I brewed it I just steeped at the end of the boil. I recommend getting the alkalinity at the start of the mash to around 20. Hope you enjoy the beer please let us know how it works out.

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Eric
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Re: How accurate are ph indicator strips?

Post by Eric » Sun Oct 25, 2020 11:56 am

Top Cat wrote:
Sat Oct 24, 2020 5:39 pm
Hi guys.
Please find results of water analysis below

Sodium as Na, mg/L 32.0
Potassium as K, mg/L 4.0
Magnesium as Mg, mg/L 7.8
Calcium as Ca, mg/L 51.8
Chloride as Cl, mg/L 51.9
Nitrate as NO3, mg/L 16.4
Phosphate as PO4, mg/L 4.5
Sulphate as SO4, mg/L 34.6
Total alkalinity as CaCO3, mg/L 92
pH 7.22
Conductivity uScm-1@20c 411

For my next brew I intend to try Dennis Kings Galaxy Delight, a strong well hopped pale ale, that uses malts and yeast I’ve never tried before.
I’d like to ask for your help on adjusting 36 ltrs of water for this particular beer.
A great start to treating your water, an accurate snapshot. Have you a cheap TDS meter? If so, use it to monotor the consistency of your water supply. Water supplies in Britain are mostly consistent, but some aren't and the heavy rain at the beginning of this month did infiltrate and dilute many otherwise stable supplies. My own is exceptionally prone to this, though a quick reading with a TDS meter enables me to simply compensate.

As Dennis advised, alkalinity is foremost candidate for adjustment. A Salifert KH test kit will enable its measurement on the day to allow accurate adjustment. From your report and as Dennis suggests it will be necessary to reduce alkalinity by 72 mg/L. As 1 ml of CRS will neutralise 183 mg of alkalinity measured as CaCO3 it is necessary to add (72/183=) 0.41 ml of CRS to each litre of liquor used.

CRS is claimed to be an equi-normal mix of sulphuric amd hydrochloric acids, so for each mg reduction in alkalinity as CaCO3, will increase chloride content by 0.354 mg and sulphate content by 0.48 mg. For 72 mg/L alkalinity reduction, chloride content in your treated liquor would increase roughly by 25 mg/L and sulphate by 35 mg/L.

With the calcium level in your less alkaline liquor raised above 100 mg/L by salt additions you should find the mash pH to be in your target region.
Without patience, life becomes difficult and the sooner it's finished, the better.

Top Cat
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Re: How accurate are ph indicator strips?

Post by Top Cat » Sun Oct 25, 2020 1:34 pm

orlando wrote:
Sun Oct 25, 2020 8:18 am
Click on JBK links, top left, 5th topic down, water treatment. Review that first
Cheers Orlando.
Very helpful, I never noticed it before, been messing around with Graham’s water calculator this morning, will use the info on it.

Top Cat
Steady Drinker
Posts: 87
Joined: Mon Nov 06, 2017 9:59 pm

Re: How accurate are ph indicator strips?

Post by Top Cat » Sun Oct 25, 2020 1:56 pm

Eric wrote:
Sun Oct 25, 2020 11:56 am
Top Cat wrote:
Sat Oct 24, 2020 5:39 pm
Hi guys.
Please find results of water analysis below

Sodium as Na, mg/L 32.0
Potassium as K, mg/L 4.0
Magnesium as Mg, mg/L 7.8
Calcium as Ca, mg/L 51.8
Chloride as Cl, mg/L 51.9
Nitrate as NO3, mg/L 16.4
Phosphate as PO4, mg/L 4.5
Sulphate as SO4, mg/L 34.6
Total alkalinity as CaCO3, mg/L 92
pH 7.22
Conductivity uScm-1@20c 411

For my next brew I intend to try Dennis Kings Galaxy Delight, a strong well hopped pale ale, that uses malts and yeast I’ve never tried before.
I’d like to ask for your help on adjusting 36 ltrs of water for this particular beer.
A great start to treating your water, an accurate snapshot. Have you a cheap TDS meter? If so, use it to monotor the consistency of your water supply. Water supplies in Britain are mostly consistent, but some aren't and the heavy rain at the beginning of this month did infiltrate and dilute many otherwise stable supplies. My own is exceptionally prone to this, though a quick reading with a TDS meter enables me to simply compensate.

As Dennis advised, alkalinity is foremost candidate for adjustment. A Salifert KH test kit will enable its measurement on the day to allow accurate adjustment. From your report and as Dennis suggests it will be necessary to reduce alkalinity by 72 mg/L. As 1 ml of CRS will neutralise 183 mg of alkalinity measured as CaCO3 it is necessary to add (72/183=) 0.41 ml of CRS to each litre of liquor used.

CRS is claimed to be an equi-normal mix of sulphuric amd hydrochloric acids, so for each mg reduction in alkalinity as CaCO3, will increase chloride content by 0.354 mg and sulphate content by 0.48 mg. For 72 mg/L alkalinity reduction, chloride content in your treated liquor would increase roughly by 25 mg/L and sulphate by 35 mg/L.

With the calcium level in your less alkaline liquor raised above 100 mg/L by salt additions you should find the mash pH to be in your target region.
Thanks Dennis/Eric.
Glad you remarked on the late hopping Dennis, as that’s my preferred way of increasing hop intensity.
As for the alkalinity, I have CRS treatment from the MaltMiller, Calcium Sulphate and Calcium Chloride, so I’m good to go following the treatment advice given to me by Eric.
I’ll divulge the figures and hope everything fits into place.
When I’ve sampled the brew Dennis, I will post in the appropriate topic.

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