pH meter storage solution drying out and turning white?

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk:

MagicMatt

Brewmathemagician
Joined
Feb 3, 2014
Messages
1,072
Reaction score
246
Location
The Crescent City
I have a Hanna pHep pH meter, and bought storage solution from them (along with cleaning solution and buffer solutions).

After every use I pour several drops of the storage solution into the well in the cap and close tightly on the meter. The next time I go to use it, there is a dried white flaky substance that has leaked out of the cap a bit, and when removing the cap it is all over the inside as well. I am assuming this is the storage solution.

So why is this happening? I would think the solution should remain liquid since the electrode should be kept moist. Any help is appreciated!
 

Gavin C

Well-Known Member
Lifetime Supporter
Joined
Jul 21, 2014
Messages
7,035
Reaction score
3,480
Location
Dallas
I have a Hanna pHep pH meter, and bought storage solution from them (along with cleaning solution and buffer solutions).

After every use I pour several drops of the storage solution into the well in the cap and close tightly on the meter. The next time I go to use it, there is a dried white flaky substance that has leaked out of the cap a bit, and when removing the cap it is all over the inside as well. I am assuming this is the storage solution.

So why is this happening? I would think the solution should remain liquid since the electrode should be kept moist. Any help is appreciated!
As the storage solution is saturated potassium chloride i believe.

Over time, if any evaporation of the solution occurs or I guess if any cooling of the solution occurs, KCL will crystalize and grow out from the cap and the device interface.

That would be my guess.
 

day_trippr

Well-Known Member
Joined
May 31, 2011
Messages
37,370
Reaction score
20,211
Location
Stow, MA
fwiw, my experience with a 98128 (pHep5) over few years is this happens all the time but has not had any apparent effects on the meter.
I try to refresh the storage cap monthly or when I pull it out for use so I catch it still "moist" but I do miss on occasion and that's when I'm greeted by the dried up white stuff...

Cheers!
 
OP
MagicMatt

MagicMatt

Brewmathemagician
Joined
Feb 3, 2014
Messages
1,072
Reaction score
246
Location
The Crescent City
Thanks for the replies guys. So I guess a follow up question is what can I do to prevent it, or is it a problem not worth worrying about?
 

Gavin C

Well-Known Member
Lifetime Supporter
Joined
Jul 21, 2014
Messages
7,035
Reaction score
3,480
Location
Dallas
Thanks for the replies guys. So I guess a follow up question is what can I do to prevent it, or is it a problem not worth worrying about?
I don't believe it's anything to be too worried about. The solution should still be saturated as your losing fluid and salts to the crystallization. The bulb is still immersed in a saturated KCl solution.

I could be 100% wrong though.

The mess would bug me enough to change out the fluid. Perhaps don't fill the cap quite so full. That could minimize this minor issue.
 
OP
MagicMatt

MagicMatt

Brewmathemagician
Joined
Feb 3, 2014
Messages
1,072
Reaction score
246
Location
The Crescent City
Well that is what I'm worried about.....there is no sponge in the cap. There is just a little well of sorts that the actual probe goes into, and that's what I've been filling (with about 4 or 5 drops, which makes it full) of solution. When I cap it, I can only assume that the displacement caused by the probe pushes some (most?) of the solution into the rest of the cap.

But because of this, every single time I've opened the cap (even just a week later), it is bone dry inside. I'm following the instructions in terms of how to apply the storage solution, but this seems like a really ineffective method of keeping the probe wet.

What am I missing? Surely they didn't design this to have this shortcoming?
 

emsroth

Well-Known Member
Joined
Feb 19, 2012
Messages
82
Reaction score
5
Bump

Any updates? New to pH myself and I have the same problem.

Was there any special cleaning required before using again? Hanna care guide says 30 minute soak in cleaning solution or an hour soak in storage solution to reactivate. Obviously I have a mash going right now.
 

mabrungard

Well-Known Member
Lifetime Supporter
Joined
Feb 22, 2011
Messages
6,018
Reaction score
1,966
Location
Carmel
If the probe was stored in storage solution and it dried out, the main problem is the loss of hydration. There isn't likely to be a need for 'cleaning solution' since that is intended for removing films and organics. The main fix for a dried out probe is to get it back into storage solution so that it can rehydrate and help restore the ionic balance for the salt bridge. It will take hours, if not days, for the probe to be restored.

As you may have already found, even with a cap on the probe, it can still eventually dry out. You either have to refresh the solution occassionally, or store the probe in a big bottle of solution. I just cut a hole in the cap of storage solution and inserted the probe into that bottle of solution.
 

Rev2010

Well-Known Member
Joined
Jan 3, 2011
Messages
3,246
Reaction score
636
Location
Brooklyn
I've found for pH meters that don't have a good rubber ring around the base to create a good seal that using a piece of tape wrapped fully around the area where the cap meets the body helps to seal in the moisture much better. Of course, always store it in upright standing orientation as well.


Rev.
 

Mybuddypete

Well-Known Member
Joined
Jul 10, 2013
Messages
46
Reaction score
16
Make sure to store your meter upright, don't store it laying on it's side.
 

ScrewyBrewer

ezRecipe - Beer Recipe Design Made Easy!
Lifetime Supporter
Joined
Jun 5, 2010
Messages
1,861
Reaction score
478
Location
New Jersey
I've eliminated the white crusties being formed by storing my pH meter in a small glass filled with storage solution. I then wrap plastic wrap around the meter and the glass holding it in place with two small elastic bands. The idea is to keep the storage solution sealed off from air and it works well.

ph meter-stor.jpg
 

ScrewyBrewer

ezRecipe - Beer Recipe Design Made Easy!
Lifetime Supporter
Joined
Jun 5, 2010
Messages
1,861
Reaction score
478
Location
New Jersey
Bump

Any updates? New to pH myself and I have the same problem.

Was there any special cleaning required before using again? Hanna care guide says 30 minute soak in cleaning solution or an hour soak in storage solution to reactivate. Obviously I have a mash going right now.
I've had my Hanna pH meter over four years now and have replaced the probe three times. Below are the steps I use, and Hanna item numbers, that keep a Ph meter in top working condition.

Soak probe in cleaning solution for an hour [HI7061]
Calibrate and take wort pH readings at 77F [HI7007-HI7004]
Soak probe in cleaning solution for an hour [HI70300]
Store Ph meter away with probe submerged in storage solution

...repeat the above steps as needed...
 

ajdelange

Well-Known Member
Lifetime Supporter
Joined
Aug 5, 2010
Messages
11,959
Reaction score
2,730
Location
McLean/Ogden
Thought I had responded here but guess not. KCl solution is one of two liquids (the other being He II) which exhibit "creep" i.e. the ability to climb the walls of a vessel containing them. Thus it isn't enough to seal in the usual sense. You must make sure the seal is a very good one. It is easy for the stuff to slip around the edges of the typical caps found on pH electrodes. The small bottles with a hole and o-ring in the caps are better but some will often still make it through.

In any case it's nothing to worry about. Just blast the crystals off with a squirt of DI water and replace the lost solution from time to time.
 

tdibratt

Active Member
Joined
Mar 29, 2016
Messages
31
Reaction score
2
i have the same problem. I fill the cap (no sponge in it) and within 2 weeks I go check it's bone dry and white. What a poor design
 

ScrewyBrewer

ezRecipe - Beer Recipe Design Made Easy!
Lifetime Supporter
Joined
Jun 5, 2010
Messages
1,861
Reaction score
478
Location
New Jersey
i have the same problem. I fill the cap (no sponge in it) and within 2 weeks I go check it's bone dry and white. What a poor design
I put a few ounces of storage solution in a small glass and put my pH meter in it. Then I wrap plastic wrap around the meter and glass to seal in the solution and prevent it from evaporating. Using two small elastic bands to hold everything in place. That will prevent the meter bulb from drying out even after months of storage.
 
Top