Apex in-sump salinity calibration

[psumms]

My Apex salinity reading has drifted over the past few months, not far, but enough to give it a quick calibration. My Hanna gives a solid 35ppm. I'm sure I've previously done a manual calibration where I've just left the probe in the sump and run the calibration - granted, I've not done one in maybe 18 months. But now it seems the manual calibration steps want the 53,000 µS/cm solution. Is there a way to still do this? I just want to tell my probe the salinity level is at 35ppm!

 

[gbroadbridge]

My Apex salinity reading has drifted over the past few months, not far, but enough to give it a quick calibration. My Hanna gives a solid 35ppm. I'm sure I've previously done a manual calibration where I've just left the probe in the sump and run the calibration - granted, I've not done one in maybe 18 months. But now it seems the manual calibration steps want the 53,000 µS/cm solution. Is there a way to still do this? I just want to tell my probe the salinity level is at 35ppm!

53mS is the same as 53,000uS is the same as 35ppt.

If you're sure your tank is at 35ppt just calibrate using it.

 

[All_talk]

I don't think the salinity probe calibration in the Apex will let you use a standard other than 52ms/35ppt. I like to run my tank at 34.5 to 35ppt but for calibration I will adjust it to 35ppt per a trusted reference (precision hydrometer in my case), and calibrate to the tank water. For me calibrating to the tank if far more stable than that to a reference solution, recent graph included for reference.