Author Topic: pH meter questions  (Read 2025 times)

Offline denny

  • Administrator
  • I must live here
  • *****
  • Posts: 11670
  • Noti OR [1991.4, 287.6deg] AR
    • View Profile
    • Dennybrew
Re: pH meter questions
« Reply #15 on: November 19, 2010, 11:40:36 AM »
What? No one have any ideas about the slime?

Wasn't that a bad horror movie?  ;)
Life begins at 60.....1.060, that is!

www.dennybrew.com

The best, sharpest, funniest, weirdest and most knowledgable minds in home brewing contribute on the AHA forum. - Alewyfe

Offline euge

  • Official Poobah of No Life.
  • *
  • Posts: 7225
  • Estilo Casero
    • View Profile
Re: pH meter questions
« Reply #16 on: November 19, 2010, 11:43:57 AM »
LOL.

I'm a bit concerned though. I don't like slime.
The first principle is that you must not fool yourself, and you are the easiest person to fool. -Richard P. Feynman

Offline denny

  • Administrator
  • I must live here
  • *****
  • Posts: 11670
  • Noti OR [1991.4, 287.6deg] AR
    • View Profile
    • Dennybrew
Re: pH meter questions
« Reply #17 on: November 19, 2010, 12:03:45 PM »
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.
Life begins at 60.....1.060, that is!

www.dennybrew.com

The best, sharpest, funniest, weirdest and most knowledgable minds in home brewing contribute on the AHA forum. - Alewyfe

Offline euge

  • Official Poobah of No Life.
  • *
  • Posts: 7225
  • Estilo Casero
    • View Profile
Re: pH meter questions
« Reply #18 on: November 19, 2010, 12:07:55 PM »
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. :P
The first principle is that you must not fool yourself, and you are the easiest person to fool. -Richard P. Feynman

Offline mabrungard

  • Senior Brewmaster
  • ******
  • Posts: 1101
    • View Profile
    • Bru'n Water
Re: pH meter questions
« Reply #19 on: November 19, 2010, 02:13:16 PM »
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.
Martin B
Carmel, IN

BJCP National
Foam Blowers of Indiana (FBI)

Brewing Water Information at:
https://sites.google.com/site/brunwater/

Like Bru'n Water on Facebook for occasional discussions on brewing water and Bru'n Water

Offline denny

  • Administrator
  • I must live here
  • *****
  • Posts: 11670
  • Noti OR [1991.4, 287.6deg] AR
    • View Profile
    • Dennybrew
Re: pH meter questions
« Reply #20 on: November 19, 2010, 02:42:15 PM »
I suppose that high percentage phoshoric acid could be used

I wonder if undiluted StarSan might work.
Life begins at 60.....1.060, that is!

www.dennybrew.com

The best, sharpest, funniest, weirdest and most knowledgable minds in home brewing contribute on the AHA forum. - Alewyfe

Offline BrewArk

  • Brewer
  • ****
  • Posts: 452
  • Rick - Newark, California
    • View Profile
    • BrewArk
Re: pH meter questions
« Reply #21 on: November 19, 2010, 02:55:44 PM »
<snip>
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. 

Muriatic acid is available @pool supply outlets and many hardware stores.  It is just another name for hydrochloric.
Beer...Now there's a temporary solution!

Na Zdraví

Offline bluesman

  • Global Moderator
  • I must live here
  • *****
  • Posts: 8678
  • Delaware
    • View Profile
Re: pH meter questions
« Reply #22 on: November 19, 2010, 03:20:54 PM »
I suppose that high percentage phoshoric acid could be used

I wonder if undiluted StarSan might work.

Denny,

Have you tried contacting the manufacturer?

They should be able to answer this question. Maybe they can also give some other options for probe storage.

Just a thought.
Ron Price

Offline denny

  • Administrator
  • I must live here
  • *****
  • Posts: 11670
  • Noti OR [1991.4, 287.6deg] AR
    • View Profile
    • Dennybrew
Re: pH meter questions
« Reply #23 on: November 19, 2010, 03:56:09 PM »
I suppose that high percentage phoshoric acid could be used

I wonder if undiluted StarSan might work.

Denny,

Have you tried contacting the manufacturer?

They should be able to answer this question. Maybe they can also give some other options for probe storage.

Just a thought.

I'm not having any problems (knock on wood!) with using storage solution.  My comment was in response to Martin mention phosphoric acid.
Life begins at 60.....1.060, that is!

www.dennybrew.com

The best, sharpest, funniest, weirdest and most knowledgable minds in home brewing contribute on the AHA forum. - Alewyfe

Offline James Lorden

  • Brewer
  • ****
  • Posts: 337
  • Forest Hill, MD
    • View Profile
Re: pH meter questions
« Reply #24 on: November 26, 2010, 01:55:18 PM »
I have had is meter for a long time.  I know the electrode needs to be replaced occasionally but mine seems to still work fine (over a year old).  What is the best indicator that a replacement is needed?
James Lorden
Beer Drinker Beer Maker & Beer Judge

Offline punatic

  • Official Poobah of No Life.
  • *
  • Posts: 4582
  • Puna District, Hawaii Island (UTC -10)
    • View Profile
Re: pH meter questions
« Reply #25 on: November 26, 2010, 02:43:17 PM »
Cleaning your pH probe with a strong acid or base or any kind of harsh cleaning solutions is a bad idea! 

What causes pH probes to slow down and fail is the buildup of scale on the bulb.

Mix up a dilute citric acid solution and soak the probe overnight in that.  Use 1/2 tsp of citric acid crystals dissolved in 50mL of DI water.  Citric acid crystals are available at your LHBS.

When I notice a pH probe taking longer than usual to settle on a value I will store the probe in a 4 pH buffer overnight.  If that doesn't work I will do a citric acid soak.

Also, do not "scrub" the bulb on your pH probe with anything even slightly abrasive.  Use a fine water jet, like the one delivered by a squeeze bottle, to do the mechanical cleaning of the bulb.  Then pat the bulb dry with a soft cloth or soft paper towel.

If your pH meter/probe has a cap to cover the probe end with, keep the cap filled with KCl probe storage solution.  If you store you probe in a beaker or flask you may prefer to store it in a 7 pH buffer solution.  A 7 pH buffer solution is almost as good as a KCl solution for storage.  If you use a KCl solution in an open container you will find the liquid evaporates and makes a big crystaline mess.

It is VERY important not to let your pH probe dry out. If you have no storage solution keep it wet with plain water.

I use a Hach HQ40d pH/Conductivity/LDO portable meter

But I use it for more than just my hobbies.
There is only one success: to be able to spend your life in your own way.


AHA Life Member #33907