PH probe help

gaboon

gaboon

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I got 2 no-name brand PH probes. Never set one up so 2 questions..

1. They have a liquid in them, do I leave it in there?

2. I got the calibration fluid as well. How do I calibrate them?

I was told to leave them in the tank for 5 days before calibrating. Using a aquatronica controller if that helps.

Shot!
 
gaboon said:
1. They have a liquid in them, do I leave it in there?

2. I got the calibration fluid as well. How do I calibrate them?

I was told to leave them in the tank for 5 days before calibrating. Using a aquatronica controller if that helps.

Shot!
Click to expand...

Are you talking about the liquid that keeps them wet, if so it will be a storage solution to stop them getting dry, rinse in RO water and then place them in your tank.

You will have to use your controller to calibrate them, don't know the controller can't help with this one. Is it the computer or a stand alone controller.
 
Gonna sound like a real twit now, pulled the cap off but its empty so I'm assuming it dried/leaked out. The probe itself has liquid inside it. Is that normal?
 
It is the tip that we are more worried about, yes I think their is some kind of fluid in the rest of the probe. The glass ball on the end needs to be soaked first before you can calibrate it. It is normally transported in a storage solution that in Ph neutral. Just leave it in some RO water or even PH7 solution for 24 hours then try calibrate it.
 
Thanks Shaun, downloaded the manual for the controller, recommends soaking a aquatronica probe in tank water for 5 days, 10 days if no storage solution. Do you think its different for the no-name brands?
 
Shaun said:
Just leave it in some RO water or even PH7 solution for 24 hours then try calibrate it.
Click to expand...

If I may... NEVER leave a pH probe in RO water - it will ruin it very quickly. Soak the probe (tip) in pH 4 or pH 7 solution for at least 24 hours before calibration.

Do you know how old these probes are? The reason I'm asking is that probes have a limited shelf life, and I'm just concerned that you might have bought old probes - given that the storage solution has dried up...

I got the calibration fluid as well. How do I calibrate them?
Click to expand...

Don't know how your controller works, but here's a "generic" for manual adjustment...
  • Ensure that all buffers and the RO rinse water is close to 25°C before you start.
  • First place the probe in pH 7.00 (or 7.01) buffer (calibration solution), wait until the reading stabilises, and then adjust the "STANDARD" or "STD" trimmer until it the display reads 7.00 (or 7.01).
  • Rinse the probe in RO water, and then place it in the pH 10.00 (or 10.01) buffer, wait a few seconds until the reading stabilises and then adjust the "SLOPE" trimmer until the display reads 10.00 (or 10.01).
  • Rinse the probe in RO water and place back in the pH 7.00 buffer. The reading should stabilise very close to pH 7.00 - if it does, you're done... if not, repeat the whole process.
If the controller is microprocessor driven, you will most likely have to select "calibrate", and it should then prompt you to place the probe in one of the buffer solutions. Just follow the menu from there on, and good luck - some of those microprocessor type controllers can be a real pain to calibrate...

Just as an aside - for use in a marine tank, always calibrate in pH 7 and pH 10 buffers, and NOT in pH 4 buffer - the pH 4 value is too far away from the pH we have in out tanks (around 8.3), and even if calibrated perfectly in pH 7.0 and 4.0 buffers it could still read wrong by up to 0.5pH if then used in an alkaline solution.

Hennie
 
Reef Maniac said:
If I may... NEVER leave a pH probe in RO water - it will ruin it very quickly.
Click to expand...
What is the next best thing to store a probe in if you don't have any calibration fluid? I have stored mine in normal tap water and it will be in storage for about another 2 months.
 
Reef Maniac said:
If I may... NEVER leave a pH probe in RO water - it will ruin it very quickly. Soak the probe (tip) in pH 4 or pH 7 solution for at least 24 hours before calibration.

Do you know how old these probes are? The reason I'm asking is that probes have a limited shelf life, and I'm just concerned that you might have bought old probes - given that the storage solution has dried up...



Don't know how your controller works, but here's a "generic" for manual adjustment...
  • Ensure that all buffers and the RO rinse water is close to 25°C before you start.
  • First place the probe in pH 7.00 (or 7.01) buffer (calibration solution), wait until the reading stabilises, and then adjust the "STANDARD" or "STD" trimmer until it the display reads 7.00 (or 7.01).
  • Rinse the probe in RO water, and then place it in the pH 10.00 (or 10.01) buffer, wait a few seconds until the reading stabilises and then adjust the "SLOPE" trimmer until the display reads 10.00 (or 10.01).
  • Rinse the probe in RO water and place back in the pH 7.00 buffer. The reading should stabilise very close to pH 7.00 - if it does, you're done... if not, repeat the whole process.
If the controller is microprocessor driven, you will most likely have to select "calibrate", and it should then prompt you to place the probe in one of the buffer solutions. Just follow the menu from there on, and good luck - some of those microprocessor type controllers can be a real pain to calibrate...

Just as an aside - for use in a marine tank, always calibrate in pH 7 and pH 10 buffers, and NOT in pH 4 buffer - the pH 4 value is too far away from the pH we have in out tanks (around 8.3), and even if calibrated perfectly in pH 7.0 and 4.0 buffers it could still read wrong by up to 0.5pH if then used in an alkaline solution.

Hennie
Click to expand...

Thanks Hennie, I bought them from a reputable guy that imports from China but I've had them for about 5 months now. Adam told me they are sh!t compared to the aquatronica probes but the price difference for 2 of them was about R1500.

Will give them a bash and compare results to a test kit.

Thanks for the info:peroni:, I thought the one calibration fluid was for the tank and the other for the calcium reactor. I'll read this in a few months and laugh.
 
viper357 said:
What is the next best thing to store a probe in if you don't have any calibration fluid? I have stored mine in normal tap water and it will be in storage for about another 2 months.
Click to expand...

Water with a few drops of vinegar in it should be fine... Ideally, though they should be stored in potassium chloride.

Hennie
 
gaboon said:
... the manual for the controller recommends soaking a aquatronica probe in tank water for 5 days, 10 days if no storage solution. Do you think its different for the no-name brands?
Click to expand...

No, if the probe has really dried out it might take that long for it to reach equilibrium again - although the norm is to soak for 24 hours if the probe has been stored properly (i.e. wet...).

Hennie
 
Gaboon, if you're using one of the probes for your calcium reactor you'll calibrate that one with pH4 and pH7 since the reading within the reactor will be around 6 to 6.5. For your display you need to calibrate with pH7 and pH9 or pH10.
 
SynysterGates said:
Gaboon, if you're using one of the probes for your calcium reactor you'll calibrate that one with pH4 and pH7 since the reading within the reactor will be around 6 to 6.5. For your display you need to calibrate with pH7 and pH9 or pH10.
Click to expand...

Cool thanks, I'll get the ph4.
 
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