There was a discussion a few months ago about storing (and calibrating) pH meters.
However, I’d really like recommendations about particular models - especially the Hanna Instruments Beer Testing models.
Any opinions??
thanks
Well you want to use the General Hydroponics 7.0 pH calibration fluid for storage.
I haven’t owned a Hanna but bought an Ecotester instead. It is waterproof, accurate and only cost me about $75 at the LHS.
Example:
http://www.pulseinstruments.net/index.asp?PageAction=VIEWPROD&ProdID=2884
AFAIK the Hanna’s are a popular brand. Costly.
Is that a pH meter designed for beer? Do you have a model Name/number?
Kai
This is the link from the Hanna website for Beer pH testers
http://www.hannainst.com/usa/prods2.cfm?id=031003
let me know what you think
I don’t see why not. I’ve used it for testing my mash, water etc. As long as I keep it calibrated.
I can probably help you. I started with the Hanna 98103 but didn’t have much faith in it. I subsequently purchased a lab quality meter. I’ll run a side by side test tomorrow and post the results for you.
How much are those simple Hanna meters? If the precision is only 0.1 - 0.2 units you may be better of using colorpHast strips.
Kai
Kai I apologize I didn’t read your post fully.
It’s an Ecotester pH1 I think it has Oakton guts… whatever that means.
http://www.hydroponicsoutlet.com/Oakton-Meters-Waterproof-EcoTster-pH1-p/ok35423-00.htm
http://www.eutechinst.com/pdt-para-ph-ecotestrph1.html
For that price you can also get one that has 0.02 pH accuracy. Although it wouldn’t have ATC and automatic calibration. But I think that those features are not necessary. Here is something I wrote about selecting a pH meter for brewing: PH Meter Buying Guide - German brewing and more
Kai
Thanks for the link to your article, Kaiser.
Do you have other articles that you could please send me links to?
but what’s the bottom line on pH meters?
I want a recommendations for a good meter in the $50 range
I have had 2 of these: http://www.hannainst.com/usa/prods2.cfm?id=031003&ProdCode=HI 98128 although it was 0.01 accuracy when I got it. The first lasted several years. The second only lasted 1-2 years, but I didn’t store it in the storage solution.
Now I have a Milwaukee.
Get the calibrating solution in 16 oz bottles from your local science supply store.
The results of the test between the bench top meter (Radiometer PH 220) and the Hanna meter 98103 summarizes as follows:
Six samples were tested ranging from a PH of 6.94 to 2.70
Prior to running the test both meter probes were stored wet, in an approved storage solution.
The probes were hydrated/rinsed for 30 minutes; then were calibrated using standard buffer solutions of 4.01 and 7.01. Both meters held stable readings during calibration.
All samples were tested at 21 degrees Celsius and the probes were rinsed between tests and blotted dry.
The bench top meter was able to reach a stable reading within 32 seconds on average. The pocket meter could only obtain a stable reading on lower PH solutions and would often drift for 10 minutes, which was the cut off point for the test s. The difference between the readings of the two meters ranged on average .32
It should be noted that the drifting of the reading is what initially frustrated me about the Hanna meter. Although the drift eventually slowed to the point that I was willing to accept the reading I never trusted it and went back to PH test strips before getting the bench top meter.
Based on my experience I would suggest staying away from the lower priced meters in favor of PH test strips. If you are going to invest in a meter start by visiting Kai’s website. He has some very good information on Ph and the meter he’s using.
Hope this was helpful
mrcceo,
Thanks for sharing the test results. I assume that during the test the samples were stirred or the probes were agitated. I tend to see drifts too, but only when I don’t move the probe. Also, were the samples well buffered? I think the lab grade pH meter really shine when the sample’s pH is very weakly buffered. Soft water is a good example. But most solutions we test in brewing are strongly buffered.
David,
Keep in mind that the simple Hanna meters are advertised as replacements for strips. They seem to have a comparable accuracy. Given the precision with which we want to hit the mash pH, 5.3 - 5.6 is good, they should be acceptable. But if you are technically inclined you may look for more accuracy in the future. It is my opinion that a good simple pH meter with buffers and storage solution can be had for under $100. That is the SM101 that I mention in the article.
Kai
Kai:
I did agitate the solutions but did not buffer them. I based the testing procedures on the instructions that came with the Hanna meter since that meter’s performance was in question.
I just posted some similar questions in the equipment section, but I’ll repeat them here…I’m looking at a Milwaukee pH51 at the LHBS. According to Kai’s buyers guide, I should be looking for an accuracy of .01ish. If I read this correctly (http://www.milwaukeetesters.com/pdf/pH51.pdf), the pH 51 is only .1? All I’m really interested in is mash pH, and Kai’s writeup implies that might be OK for that that purpose. Anybody used this model?
What model of Milwaukee, Tom?
SM 102. It has a separate temperature probe and automatic calibration.
Kai likes the SM 101 because it has manual calibration. I think he had a previous meter that stopped automatically calibrating. But it doesn’t have a temperature probe.
I like the temperature probe to make sure I’m not putting the pH probe in wort that’s too hot. Of course you can get your own separate thermometer! And you probably already have one of those.
Brew on!
Well, I think I’m gonna pull the trigger on the pH51. May not be the best meter out there, but it looks like it will fulfill my needs…and besides, my BIL is paying for it! 
Denny, the resolution and variance for that model are both 0.1 pH. I don’t really see where a resolution to a hundredth in homebrewing would help any more than a tenth. But, always nice to have.
That unit has a manual callibration screw and replaceable electrode. Nice!
If you’re just looking to check mash pH and maybe also boil pH an accuracy of +/- 0.1 should be fine. If you have greater resolution you can also use it to check your beer pH and detect if you have problems with autolysis for example. That causes an unusually high rise in beer pH after fermentation. I never noticed anything dramatic but I thought of it when I opted for higher precision model. I also needed better precision to do the mash pH experiments I did.
Kai