Salinity

[bscecil]

I have tested my salinity with 3 different devices and get 3 different levels. The only one that makes sense is the refracto scope meter, since it measures the saltwater straight out of the box as 1.025. The float tester says it is extremely high and the electronic dip meter says it is extremely low. Unless someone has an answer I’m ignoring the other two and sticking with the refracto light scope meter.

 

[PeterC99]

I have tested my salinity with 3 different devices and get 3 different levels. The only one that makes sense is the refracto scope meter, since it measures the saltwater straight out of the box as 1.025. The float tester says it is extremely high and the electronic dip meter says it is extremely low. Unless someone has an answer I’m ignoring the other two and sticking with the refracto light scope meter.

Go get it tested at your LFS.

 

[bushdoc]

Refractometer should be most reliable if calibrated.
what brand are those devices? Can you post pics?

 

[vetteguy53081]

If any I would trust refract but try having an LFS test and see which coincides with yours and if they have calibration fluid, see how your instrument reads with that fluid

 

[bscecil]

Chaoos Digital Salinity Tester, 5 in 1 TDS/PH/EC/Temp&Salinity Tester Waterproof LCD Saltwater Meter​

Coralife Energy Savers ACLAF877 Deep Six Hydrometer​

Aichose Brix Refractometer with ATC, Dual Scale - Specific Gravity & Brix, Hydrometer​

 

[Gtinnel]

Besides having a lfs test your water you can also make a solution with a known salinity using table salt and rodi water to know which device is correct.

 

[vtecintegra]

Get the tropic marin hydrometer. No guessing if it's calibrated or accurate.

 

[PatW]

Refractometers are easy to calibrate. You can buy a bottle of calibration fluid and it will last a long time.

 

[mixeras]

I literally having same problem today. I calibrated my hanna and my apex salinity probe. I bought water that is know to 35 ppt. Hanna is telling me it's 31.5. Apex is telling me it's 38. Recalibrated both interments twice.

 

[Randy Holmes-Farley Verified Community Expert]

I literally having same problem today. I calibrated my hanna and my apex salinity probe. I bought water that is know to 35 ppt. Hanna is telling me it's 31.5. Apex is telling me it's 38. Recalibrated both interments twice.

The Hanna and the Apex are the same type of device and should read the same solutions the same, even the calibration solutions.

What calibration fluids are you using? Same or different ones? Did they read the calibration fluids correctly after calibration?

Temp can be an issue with the APEX. it needs to know the temp of the calibration fluid, but its temp sensor might be in your tank water. Sometimes that needed temp correction on the APEX is misadjusted or even turned off.

 

[EricR]

Also, Hanna EC does temp compensation as well so I vote:
- get calibration solution to 77 degrees
- let Hanna adjust to the temp before calibrating

...meaning, it should handle temp variance but minimize that part during calibration

P.S. I have way better results with Randy's DIY conductivity standard than I did with the Hanna packets