Due to the generosity of my wife and BIL, I’ve got bucks to burn at the LHBS (well, gift certificates, anyway). I’m totally stocked up on brewing supplies, so I think I’m gonna pick up a pH meter. The one he sells is the Milwaukee pH51. Anybody have any experience with this brand? And any tips you can give me for using it? I assume I’ll want to pull a sample and cool it down as opposed to just sticking the meter in the mash?
This seems to be the Milwaukee equivalent to the Hanna pHep meters we discussed here: http://www.homebrewersassociation.org/forum/index.php?topic=1266.0
Kai
Thanks, Kai. I just noticed that thread and posted some questions there.
i just saw the milwaukee ph51 on e-bay for 49.50, the better one is the ph56 it has accuracy of + - 0.01 and auto temp for 64.95 + ship 5.99
Thanks…I know I can get it a lot cheaper on the internet, but I’ve got beaucoup gift certificates for the LHBS. I’m just gonna get what he’s got.
Hey Denny,
I have a Milwaukee ph meter, different model number though. You are right that you do not want to just stick the meter into the hot mash. Pull out a sample and let it cool down.
You will also want to buy bottles of the calibration solution and storage solution.
Also, get yourself a squirt bottle. I finally got a home pH meter and thought for a minute that, hey I need something to rinse off the electrode. I often use one at work and it is just second nature that the squirt bottle is always there for electrode rinsing. I got mine conveniently on campus and filled it with RO water from the lab. A squirt bottle (ketchup, mustard, etc. ) from a cooking/restaurant supply store would be a good substitute
That’s a good idea with the bottle. I rinse mine in the sink and use an old soft toothbrush to gently clean the electrode. I also auto-calibrate once it shows a variance of 0.10 pH in clean storage solution. Gets used all the time, so when I have to calibrate it too often then a cleaning is certainly needed.
I just fill a cup with R/O water from the tap to rinse the electrode before and after testing a sample.
Kai
Thanks, Tom. I got the calibration and storage solutions when I bought the mer from Jim.
All this talk about pH meters has me adding it to my wish list. Nothing like good QA during the brewing process to assure better beer.
I’ve dusted off my pH meter. Has been in storage solution for the last 7 or so months. A couple weeks ago I pulled it out to check and a bunch of slime was growing in the cap. I cleaned and tested the meter with new 7.0 solution. Read 7.4 so it got calibrated. Fine. Just checked it again and more slime. Read 7.8 but I briefly soak the cap and probe in everclear and recalibrate.
Tested it against a known solution and it is accurate.
What is this slime? I don’t see anything in the bottle of storage solution which looks as clean as the day I bought it.
Denny, I used a Milwaukee ph51 nearly every day for about 6 months, a while back. Its build is good and it’s accurate enough for most brewers. I actually know two brewpubs that use that exact ph meter (and always Milwaukee meters). I recently upgraded to a Milwaukee SM101 and I’ve been impressed with this meter as well. Enjoy
Jay, thanks so much for the personal data point. I’ve been really happy with mine so far. Like you say, the resolution is plenty good enough for my uses.
What? No one have any ideas about the slime?
Wasn’t that a bad horror movie? 
LOL.
I’m a bit concerned though. I don’t like slime.
What about an Oxiclean/PBW soak for the cap? Then some StarSan? Don’t know how it would effect the probe if you tried it on that, though. It might work.
That’s a pretty good idea. I’m thinking the little “wick” part of the probe might have a contamination of some sort.
Won’t be sticking it in my fermenters or anything like that LOL. Never would any way but it’s always something isn’t it…
Makes life interesting. 
From all the indications on pH meter care, it appears that pH meter probes should be kept wet with a potassium chloride solution. Apparently, Hanna’s pH probe storage solution is KCl. Hanna is one of the major inexpensive meter producers.
You can purchase the probe storage solution commercially. You can also make up your own solution by disolving about 22 grams of KCl in 100 ml of distilled water (I’d say that RO water is close enough to DI water).
By the way, all pH probe manufacturers state that pH probes should not be stored in plain DI or RO water since you’ll leach the ions out of the probe and kill it. Got to have the KCl in there.
For probe cleaning, I use a strong lye (NaOH) solution to remove base soluble deposits. I use the Red Devil drain cleaner for my lye. Just remember its not food grade and you’ll want to make sure its rinsed off well.
Unfortunately, I don’t have any strong acids at home such as nitric or hydrochloric, but a dip in either of those would help remove acid soluble deposits. I suppose that high percentage phoshoric acid could be used, but all I have now is 88% lactic and its not a strong acid. I suppose its better than nothing. The strong base and strong acid washes are typical cleaning regimens for the probes.