Adjusting the water but PH was really low

[frettfreak]

So i have started to get into adjusting my water more. Still readin about it and learning but think i know enough to start now.

I have my water report from ward labs. inputted all the info into the sheet. and started stepping through all the pages.I was doing a pale and targeted a profile of "yellow balanced". I diluted my tap water with 50% RO water to bring down some ion concentrations, and built up from there. Part of my calculations was adding 1ml of lactic acid to the mash.

Once i mashed in, i let it set for a couple minutes and grabbed a sample to test PH (i have the HI 9813-6 meter from hannah, was calibrated correctly) and it came out at 4.9. I waited a little longer and tested again with the same result. The strange part is, i tested this BEFORE i put the acid in (which would have made ph go down even more) so i never even put hte acid into the mash.

Here is the malts i used:
Pale (3.5srm) 7 lbs
golden promise 7 lbs
1lbs 4 oz c40
8oz honey malt

Mashed with 6.15 gallons of water and sparged with 3.72

Here is the water report:

pH 8.1

Total Dissolved Solids (TDS) Est, ppm 317

Electrical Conductivity, mmho/cm 0.53

Cations / Anions, me/L 5.0 / 4.6

ppm

Sodium, Na 64

Potassium, K 2

Calcium, Ca 34

Magnesium, Mg 5

Total Hardness, CaCO3 106

Nitrate, NO3-N 1.8 (SAFE)

Sulfate, SO4-S 23

Chloride, Cl 58

Carbonate, CO3 < 1.0

Bicarbonate, HCO3 87

Total Alkalinity, CaCO3 73

Total Phosphorus, P 0.04

Total Iron, Fe < 0.01

Here is a link to the brun water sheet in my google drive:

https://docs.google.com/spreadsheets/d/1zGvxprg-oaQSMbFtNuW-OtVeT82rBBzbSmNyPvzPtIo/edit?usp=sharing

what other information Would anyone need from me to point me in the direction of what i am doing wrong?

 

[SC_Ryan]

Sounds like a fishy reading to me

 

[frettfreak]

Sounds like a fishy reading to me

What reading sounds fishy?

 

[ajdelange]

I'd cast a jaundiced eye on the pH meter. It's very unlikely that you would get mash pH as low as 4.9 with that grain bill and water without adding a considerable amount of acid. I note that the meter you are using only reads to 0.1. That isn't really precise enough for brewing but even blaming the precision we could only suggest that the mash pH was actually 5.0 and that's still too low for that grist. It would probably be a good idea to do a stability check on your meter. See https://www.homebrewtalk.com/f128/ph-meter-calibration-302256/

 

[frettfreak]

sounds like a fishy reading to me

nvm...

 

[frettfreak]

I'd cast a jaundiced eye on the pH meter. It's very unlikely that you would get mash pH as low as 4.9 with that grain bill and water without adding a considerable amount of acid. I note that the meter you are using only reads to 0.1. That isn't really precise enough for brewing but even blaming the precision we could only suggest that the mash pH was actually 5.0 and that's still too low for that grist. It would probably be a good idea to do a stability check on your meter. See https://www.homebrewtalk.com/f128/ph-meter-calibration-302256/

While i would have also thought that, this meter is cared for properly, was pH'd before and after (just to double check, cause i thought maybe the adjustment knobs got moved accidentally maybe??) and it was spot on. I tested with 4.0 and 7.0. I realize it could be a slight bit more accurate, but if i was with in .1 up or down of my target 5.4 ph i really wouldnt have been concerned. This meter has a cal-check function, i will test with the solution and see what it says. I read your post (and have in the past too.. thanks for all the great info!). I will also do a stability check as you suggest and see what that comes up with and report back. Thanks for the help!

 

[frettfreak]

I'd cast a jaundiced eye on the pH meter. It's very unlikely that you would get mash pH as low as 4.9 with that grain bill and water without adding a considerable amount of acid. I note that the meter you are using only reads to 0.1. That isn't really precise enough for brewing but even blaming the precision we could only suggest that the mash pH was actually 5.0 and that's still too low for that grist. It would probably be a good idea to do a stability check on your meter. See https://www.homebrewtalk.com/f128/ph-meter-calibration-302256/

AJ, quick question on your stability test procedures. Do i need to leave the probe in the solution the entire time, and just check it every few minutes or do i take the probe out, put the cap on (with storage solution) and re-submerge the probe in calibration solution every time?

 

[ajdelange]

Actually, that's a very good question. It shouldn't make a difference really but the case where you take a reading, rinse the electrode, put its cap back on and then a few minutes later remove the cap, rinse, blot and take an additional reading better reflects your use of the electrode during an actual brewing sessionn so I suppose that's the better way to do it.

 

[frettfreak]

Actually, that's a very good question. It shouldn't make a difference really but the case where you take a reading, rinse the electrode, put its cap back on and then a few minutes later remove the cap, rinse, blot and take an additional reading better reflects your use of the electrode during an actual brewing sessionn so I suppose that's the better way to do it.

Ok. Makes sense. Well i have an hour and a half of data that i left the probe in. I will restart the test with taking it out and see what that yields. However, i MAY have discovered my issue and i am not sure how to go about it from here.

The instructions for the meter says:

To obtain accurate readings, use pH 7.01 (HI 7007) if you are going
to measure neutral or close to neutral samples, pH 4.01 (HI 7004)
if you are going to measure acidic samples or pH 10.01 (HI 7010)
for alkaline measurements

From my reading on the hatch probes you recommend it seems that they hold individual data for both sets of solutions and calculates using both numbers. Apparently the Hanna doesnt do this (???) so if i go from the 4.0 solution, rinse and blot, then 7.0 solution, i have to adjust the calibration knob for it to be accurate. Now if i go back to the 4.0 solution after that (with a rinse and blot in there as well) the reading is about .2 low (bounces between .2 low and .1 low so maybe .15??). I dont remember what solution i did last on brew day, but if it was 7.0 then my reading when i get closer to the 4.0 mark would be off correct?

I need a better meter!! lol

 

[ajdelange]

Ah, I did not catch that this is a single point calibration instrument. pH measurement requires knowledge of slope and offset. It takes two measurements to solve for those. Single point calibrations can work if, as the manual suggests, you are measuring close to the pH of the calibrating buffer. In brewing you are about half way between pH 4 and 7 which is is a big advantage if you are doing two buffer cal. and a big disadvantage if you are doing 1.

 

[frettfreak]

Kinda what i was thinking. Bummer! Well i am still gonna do the stability check as i am currently in the process of it but will be looking into getting a new meter just for brewing then. Is that Hatch meter still the best bang for your buck?

 

[ajdelange]

The popular candidates right now seem to be the Hach Pro + and Omega pens and the Milwaukee MW101 benchtop meters.

 

[frettfreak]

well, after 4+ hours of testing, i am thinking the problem has to be what we talked about with the 1 point calibration of this meter cause its STABLE as far as the resolution that i can see anyway.

4.0 every time and the temp was stable at 19.6c. At that temp and with this meter only going to a .1 resolution, I really can never know if it was swinging from 4.00 to 4.09, but was stable if nothing else.

I am just going to have to look into another meter i think. It will be interesting to do a side by side with the 2 meters too.

 

[ajdelange]

Well now that you know it is stable, i.e. reads 4.0 in 4.0 buffer even though you are uncertain as to whether the actual pH might be 4.0 ±0.05, that still doesn't explain reading 4.9 (even though it could have been seeing 5.0) when the mash pH should have been 5.3 or so. Other things to think about are buffers that aren't fresh and temperature (I assume this meter does not have ATC?).

 

[frettfreak]

does have ATC, but the samples were all cooled to room temp (around 78 +/-) just to be sure.

It might actually. I think i measured the 7.0 solution last on brew day. With the .2 difference on the calibration when i go from the 4.0 solution to the 7.0 solution, couldnt that mean that it was reading low (because we were closer to the 4.0 buffer ph) and actual PH could have been 5.1-5.2? The readings at 4.9 did bounce a little from 4.9 to 5.0 but seemed to be on 4.9 more. I hope i explained that well enough.

 

[ajdelange]

Yes, I guess that could be an explanation.

 

[frettfreak]

Yes, I guess that could be an explanation.

Wanted to let you know that the meter i had was just plain busted. I left it in a nutrient solution in the greenhouse at 5.9 ph. Solution was fully mixed, and ph was stable for at least 10 min (also the meter was PH's again this morning), left it alone for 5 min (meter wasnt touched) and came back it was at 4.2. will be looking at the hatch products to see what i am gonna pick up.

Thanks for all your help!

 

[frettfreak]

Did have a quick question AJ if you wouldnt mind... Have you ever heard of blue lab? I can get a really good deal on their combo meter from a friend and was wondering if you had heard of them and your opinion? It doesnt go down to the .00 range only .0 but it IS a dual point calibration. Here is the product.

https://www.bluelab.com/products/type/meters/combo-meter

It measures EC ad PPM to which i obviously dont need for brewing but i can get it for a really great deal.

 

[ajdelange]

No, never heard of them but apparently they serve the agricultural market primarily.

I generally try to steer people away from meters that resolution of 0.1 pH. If you need conductivity there is a meter in the Hach Pocket series that does it (at additional cost) in addition to pH though I haven't had one in hand so I don't know that it's going to be as good as the Pocket pH Pro + (or whatever it's called) but I think you can assume it's going to be about as good. Of course if 'it slices, it dices, it cubes, it chops....' the length of the list of things it does is often in inverse proportion to how well it does them.

 

[frettfreak]

No, never heard of them but apparently they serve the agricultural market primarily.

I generally try to steer people away from meters that resolution of 0.1 pH. If you need conductivity there is a meter in the Hach Pocket series that does it (at additional cost) in addition to pH though I haven't had one in hand so I don't know that it's going to be as good as the Pocket pH Pro + (or whatever it's called) but I think you can assume it's going to be about as good. Of course if 'it slices, it dices, it cubes, it chops....' the length of the list of things it does is often in inverse proportion to how well it does them.

Makes sense. My lhbs is a hydroponics shop as well. I dont need conductivity just liked the probe style meter vs the pen style.

Will just get the hatch and be done with it! Lol. Thanks again