Just got the conductivity module/probe and have some questions.

[glb]

Hi everyone. Today I took the plunge and bought the PM2 module and salinity probe. I did a lot of research and know it’s a finicky piece of equipment. I calibrated it manually after floating the conductivity solution packet in the sump to equalize temp. I don’t have a temp probe for this module (yet). I’ve had the ph probe for a while so the calibration process was pretty similar. I’ve tried to keep the cable away from other wires but that’s next to impossible. The probe is in my first sump chamber and is shielded from any micro bubbles by a filter sock. I read after I did all of this that the probe had to be perfectly dry before calibration, but I had already dipped it in some RODI (thought I read that somewhere). After calibration, the tank salinity is reading 36.8. I calibrated my refractometer, and it’s reading 33. I’ve heard these things take a while to settle. Did I mess up by not having the probe totally dry? When I calibrated it, it was probably close to some wires. Could that affect it? Should I just leave it alone and see if it stabilizes? Any tips or advice on getting the best out of this probe would be greatly appreciated!!

 

[P-Dub]

Give it a month or two. It took mine almost that long to settle.

 

[glb]

Give it a month or two. It took mine almost that long to settle.

Thanks! I’ll keep using the refractometer to keep things on track. I really hope it settles down. It’s a cool thing to track. Also, is there a way to get it to read the salinity the other way (eg 1.026)? I was wondering if apex settings would allow that.

 

[SPR1968]

I’ve had Apex and the salinity probe in place for 4 years and whenever I’ve calibrated it with the solution and add it to my tank it always reads high, like yours 36+. So I just don’t trust it.

I do however trust my Red Sea refractometer (because everything is alive and thriving) and now I use a Hanna salinity checker for the base line

So here’s what I do, when I’m happy the tank water is at 35 or thereabouts with the Hanna:

Remove the salinity probe and clean it or leave to soak in vinegar for an hour or so (if it needs cleaning)
Rinse in clean tap/rodi water and then wipe it to dry
Follow the calibration instructions but when it says put it in the solution, put it back into place in the tank.
Thats it, and it will match closely to, in my case the Hanna

They need cleaning every 3 months or so when you get an alert saying the salinity is at 50, usually when you’ve just landed or in a hotel having a beer! Lol

 

[glb]

I’ve had Apex and the salinity probe in place for 4 years and whenever I’ve calibrated it with the solution and add it to my tank it always reads high, like yours 36+. So I just don’t trust it.

I do however trust my Red Sea refractometer (because everything is alive and thriving) and now I use a Hanna salinity checker for the base line

So here’s what I do, when I’m happy the tank water is at 35 or thereabouts with the Hanna:

Remove the salinity probe and clean it or leave to soak in vinegar for an hour or so (if it needs cleaning)
Rinse in clean tap/rodi water and then wipe it to dry
Follow the calibration instructions but when it says put it in the solution, put it back into place in the tank.
Thats it, and it will match closely to, in my case the Hanna

They need cleaning every 3 months or so when you get an alert saying the salinity is at 50, usually when you’ve just landed or in a hotel having a beer! Lol

Thank you! I’ll try it! It’s brand new so I won’t need to clean it.

 

[glb]

I’ve had Apex and the salinity probe in place for 4 years and whenever I’ve calibrated it with the solution and add it to my tank it always reads high, like yours 36+. So I just don’t trust it.

I do however trust my Red Sea refractometer (because everything is alive and thriving) and now I use a Hanna salinity checker for the base line

So here’s what I do, when I’m happy the tank water is at 35 or thereabouts with the Hanna:

Remove the salinity probe and clean it or leave to soak in vinegar for an hour or so (if it needs cleaning)
Rinse in clean tap/rodi water and then wipe it to dry
Follow the calibration instructions but when it says put it in the solution, put it back into place in the tank.
Thats it, and it will match closely to, in my case the Hanna

They need cleaning every 3 months or so when you get an alert saying the salinity is at 50, usually when you’ve just landed or in a hotel having a beer! Lol

When the ape

I’ve had Apex and the salinity probe in place for 4 years and whenever I’ve calibrated it with the solution and add it to my tank it always reads high, like yours 36+. So I just don’t trust it.

I do however trust my Red Sea refractometer (because everything is alive and thriving) and now I use a Hanna salinity checker for the base line

So here’s what I do, when I’m happy the tank water is at 35 or thereabouts with the Hanna:

Remove the salinity probe and clean it or leave to soak in vinegar for an hour or so (if it needs cleaning)
Rinse in clean tap/rodi water and then wipe it to dry
Follow the calibration instructions but when it says put it in the solution, put it back into place in the tank.
Thats it, and it will match closely to, in my case the Hanna

They need cleaning every 3 months or so when you get an alert saying the salinity is at 50, usually when you’ve just landed or in a hotel having a beer! Lol

When the apex asks what solution I’m using, what should I select? The solution I used yesterday was 53000. Should I choose that even if I’m going to calibrate in the tank water?

 

[ca1ore]

I've not noted that the salinity probe requires much time to 'settle' (unlike the ORP probe). It is a little tricky to calibrate (I personally just use aquarium water as my calibration solution) and is quite susceptible to air bubbles and detritus. Usually a good shake solves things, but sometimes it needs to be cleaned. Probe is not always accurate but is it precise, so is useful in that regard. I do not use my probe readings to control anything rather trigger alerts.