A few words of warning regarding the use of Ca(OH)2 (Calcium Hydroxide) in mash water or in the mash

[cire]

I'm with @AdjunctBrewer on calibration, although, maybe in this case, it may not be vital to use three point calibration. What is important is the first calibration be done at pH 7, because it is centre scale. That adjustment moves the entire scale sideways if we think in an analogue way. The adjustment at pH 4 then adjusts the gain within the instrument, which in analogue terms widens or narrows the range of the readout.

I'm in the camp that believes only exceptional recipes will require alkalinity in a mash with soft water to brew most darker beers.

Good luck, you are making great progress.

 

[Peebee]

I catch up eventually!

Mini-mash: Yeap, confirm pH is calculated in Bru'n Water as 5.70. Actually appears to be 5.02 in practice. That is nothing to do with what I'm messing about with, it would require (theoretically - if there's enough "stuff" in the malt to react with) Calcium ions to go up by about 298mg/l to achieve that (according to Bru'n Water). Seems very (very³?) unlikely.

Erm ... well, I've nothing more to add?

 

[DuncB]

I catch up eventually!

Mini-mash: Yeap, confirm pH is calculated in Bru'n Water as 5.70. Actually appears to be 5.02 in practice. That is nothing to do with what I'm messing about with, it would require (theoretically - if there's enough "stuff" in the malt to react with) Calcium ions to go up by about 298mg/l to achieve that (according to Bru'n Water). Seems very (very³?) unlikely.

Erm ... well, I've nothing more to add?

My money is on a measurement generated wrong value. The new pH meter and retest should clarify.

 

[Peebee]

My money is on a measurement generated wrong value. The new pH meter and retest should clarify.

I wondered that last night after posting (and re-reading Cire's posts); it's a long time (years) since those "pen testers" required such care calibrating. Now-a-days the testers are just dropped into a buffer solution, it recognised the buffer, and calibrates accordingly? The probes on those pens have a finite life (about 6-18monthes) whether you use them or not. So, are any of those old-style 3-point calibrated pen-testers still in-date?

If it's over a year old, whether or not it holds calibration longer than a few minutes, bin it! A "new pH tester" is in order!

 

[DuncB]

I wondered that last night after posting (and re-reading Cire's posts); it's a long time (years) since those "pen testers" required such care calibrating. Now-a-days the testers are just dropped into a buffer solution, it recognised the buffer, and calibrates accordingly? The probes on those pens have a finite life (about 6-18monthes) whether you use them or not. So, are any of those old-style 3-point calibrated pen-testers still in-date?

If it's over a year old, whether or not it holds calibration longer than a few minutes, bin it! A "new pH tester" is in order!

He's got a Milwaukee on order.
I've got two of those cheapies calibrate and store in the correct medium. Both working fine and well over 2 years old.

 

[Peebee]

First link Google returned from searching: "ph probe lifespan"

pH Probe Replacement

Tell people yours' are okay after two years, and they will continue using them for three, whatever state they are in.

I'm stopping using then (unless for "investigation" work). The plastic single-use strips are more than adequate. Not precise enough? Try reading some of @Silver_Is_Money's or @ajdelange's threads on Mash pH ... that cures you of having too fanciful ideas about pH! The ones I've purchased for beer-making (but perhaps not for "researching" pH):

Beer pH Indicator Strips