Curious why you think the issue is with the Trident if it read the calibration fluid correctly?
That’s just it - I don’t think the Trident is reading the calibration fluid correctly (or the values of the calibration fluid are off). When you run the calibration the values always match the label on the white bottle - but that doesn’t mean that the Trident was calibrated correctly.
I watched the entire calibration process yesterday (twice), and during the calibration the values jump all over the place before settling on the values you entered. That tells me that the Trident is taking readings and then making an internal adjustment to match the values on the calibration fluid.
I ran numerous tests yesterday on my alkalinity, calcium and magnesium - using both digital and off the shelf test kits. The numbers were consistent (within 10-20ppm and 0.1 dKH). The only one that reasonably matched post-calibration was alkalinity.
Alkalinity (tested prior): 8.386 dKH
Alkalinity (calibration fluid): 8.25 dKH
Alkalinity (first test post-calibration): 8.26 dKH
Calcium (tested prior): 440ppm, 460ppm
Calcium (calibration fluid): 455ppm
Calcium (first test post-calibration): 570ppm
Magnesium (tested prior): 1260ppm, 1250ppm
Magnesium (calibration fluid): 1170ppm
Magnesium (first test post-calibration): 1152ppm
So 0.14 dKH isn’t a huge difference, but +110 to +130 calcium and -98 to -110 magnesium isn’t even remotely close or within error tollerances.