Busted Hanna pH Meter?

[TeflonTom]

Hey yo! So, I've had this Hanna pH meter for about under a year now and it hasn't had much of an issue until my last 4 brews where it was just reading far under what I typically get for my beers (5.2-5.5). This thing was starting to read closer to 4.6-5.1. I needed to calibrate what pH my new RO water system is pumping out and I gave it a try. Said it was near 6.0. I thought that was pretty low, but I couldn't be too surprised I guess. So to really try and calibrate it and get an accurate reading I opened 2 new 7.01 and 4.01 buffers to two-step. I know that my tap water is 7.7 and I give'r a rip. It read it at 7.0; try the RO water again and this reads it at 4.1! Great. Next, I wipe it down and get it calibrated again - same process. Now I know this new gallon of distilled water should be 7.0. The meter read it as 5.8. I just have no idea what the hell is going on. None of my equipment has been exposed to souring yeasts or anything and this is just nuts. Is this thing just busted or is there something else to consider?

 

[daveMN]

Your pH probe won't read DI water well or at all. You need some ions in the water for the probe to work. The actual pH of the DI water isn't going to be that critical for brewing anyway. Alkalinity is where it's at.

 

[IslandLizard]

I know that my tap water is 7.7

Tap water has no standard, the pH is unknown, varies by composition, due to seasons etc. Too many variables that will influence its pH.

I know this new gallon of distilled water should be 7.0.[...]

Nope, dissolved CO2 can quickly change that.

I opened 2 new 7.01 and 4.01 buffers

After calibrating with both, at their calibration temp, measure both buffers, 4.01 and 7.01, again. They should each read close to their respective value. If not, your probe is drifting. Recalibrate and recheck.

Echoing what @daveMN said in #2.

 

[TeflonTom]

Alright I'll recal tomorrow morning before the brew. Thanks for the tips, gents!

 

[IslandLizard]

Are you using a brewing/mash water calculator?
When using RO water, there's no mineral content, or very little, basically a blank slate.

You can check your RO water's total ion content with a cheap ($15-20) TDS meter, verifying your RO membrane is working as it should. A TDS reading under 10 or 20 is still very low on ions. A pH meter is useless for that purpose.

 

[TeflonTom]

I've just been using BrewersFriend advanced water calculator for my stuff lately. Need to get excel to upgrade to Bru'nWater. I will onvest in a TDS tomorrow, but I'll be using entirely RO water for my Kölsch tomorrow.






























































































































































































































































































































































































Are you using a brewing/mash water calculator?

 

[IslandLizard]

I've just been using BrewersFriend advanced water calculator for my stuff lately.

Brewer's Friend's calcs work fine.

Mash Made Easy is another good mash/water calc that doesn't require $$Excel:
https://mashmadeeasy.yolasite.com/
BTW, Bru'n Water (free Ed.) will also run under LibreOffice, so Excel isn't mandatory.
https://www.brunwater.com/

but I'll be using entirely RO water for my Kölsch tomorrow.

Alright!