Ph probe test off when stored in storage solution

[Tangdora]

Hi all.

Recently picked up a Hanna ph probe 98107 to server as a validation to my Neptune ph probe. I keep it stored in an old test pack with a little of the Hanna storage solution to keep the bulb fully submerse. However I tend to notice the first test after coming out the solution and drying it off always seems to be off 0.3-0.4 on the first reading. If I then let it sit in a cup of tank water for like 15mins and repeat the process of drying it off and letting the number drop back to 0. The 2nd test then seem to come a lot closer to where my Neptune probe reading is. Anyone know why this may be happing.

 

[UncommonSense]

Hi all.

Recently picked up a Hanna ph probe 98107 to server as a validation to my Neptune ph probe. I keep it stored in an old test pack with a little of the Hanna storage solution to keep the bulb fully submerse. However I tend to notice the first test after coming out the solution and drying it off always seems to be off 0.3-0.4 on the first reading. If I then let it sit in a cup of tank water for like 15mins and repeat the process of drying it off and letting the number drop back to 0. The 2nd test then seem to come a lot closer to where my Neptune probe reading is. Anyone know why this may be happing.

So the probe just sits in an open bag of storage solution? Not a o-ring sealed cap for the probe?

In either case, the probe storage solution isn’t good forever… especially in the former case, the storage solution will evaporate water off Over time…

 

[Tangdora]

So the probe just sits in an open bag of storage solution? Not a o-ring sealed cap for the probe?

In either case, the probe storage solution isn’t good forever… especially in the former case, the storage solution will evaporate water off Over time…

the hanna caps are not oringed sealed which is why I don’t bother using And I only Pour in like a 1/4 of solution into the packet that servers as my holder and that solution is replace each week with new solution from the regular product bottle that stays sealed. Will also note I don’t keep the packet and probe just sitting out in the open air. they are both stored inside an air sealed mason jar that happens to be just the right height to hold it when not in use.

 

[UncommonSense]

the hanna caps are not oringed sealed which is why I don’t bother using And I only Pour in like a 1/4 of solution into the packet that servers as my holder and that solution is replace each week with new solution from the regular product bottle that stays sealed. Will also note I don’t keep the packet and probe just sitting out in the open air. they are both stored inside an air sealed mason jar that happens to be just the right height to hold it when not in use.

Aah, that makes a lot more sense!

Hmm… do you swish your probe in the test water on the first test? Or just dunk it in and let it sit?

 

[Tangdora]

Swish until the little hourglass indicator stops flashing indicating the value has stabilized. What’s odd about the Hanna ph checker though it’s not just a glass bulb like the Neptune is has this section on it that has this little string right next to it that the instruction say to pull out 2mm if the numbers become erratic after a calibration. Not exactly sure what its function is but perhaps it’s some how it absorbing some of the solution and holding that ph maybe which is then getting diluted out by soaking it a few mins in tank water.

 

[UncommonSense]

Swish until the little hourglass indicator stops flashing indicating the value has stabilized. What’s odd about the Hanna ph checker though it’s not just a glass bulb like the Neptune is has this section on it that has this little string right next to it that the instruction say to pull out 2mm if the numbers become erratic after a calibration. Not exactly sure what its function is but perhaps it’s some how it absorbing some of the solution and holding that ph maybe which is then getting diluted out by soaking it a few mins in tank water.

That is unusual indeed! I have an old bluelab meter which uses traditional PH probes, so I can’t speak on that specific function!

Perhaps a resident chemist or other specialist on parameter testing hardware can chime in with more?

 

[Tangdora]

That is unusual indeed! I have an old bluelab meter which uses traditional PH probes, so I can’t speak on that specific function!

Perhaps a resident chemist or other specialist on parameter testing hardware can chime in with more?

Yeah it is. But this is the thing