Review on 🔬 Vee Gee Scientific STX-3 Handheld Refractometer with Salinity Scale - 0-100 Range, +/-1.0 Accuracy, 1.0 Resolution by Chris Norman

I have a Neptune Systems APEX controller for my reef tank that measures and reports salinity (conductivity) in real time, but I still rely on the VEE Gee STX-3 refractometer as the last word in this regard the salinity is really there. I check the refractometer calibration before each use with Aqua Craft Products refractometer calibration solution and the refractometer readings are right within the standard and I have not had to adjust the calibration yet. This gives me confidence that the STX-3 is consistently accurate and will hold up to calibration. I just threw away (sorry for using names) a Red Sea refractometer I bought about a year ago ($50-60) which took no more than a few minutes to calibrate (literally) and even then very much Measurements yielding inconsistent readings were taken from the same seawater sample with a difference of only a few minutes. I calibrated it every time and had to recalibrate 99 times out of 100. The VEE GEE STX-3 is roughly twice the price of the Red Sea (and others in its class), but in my humble opinion it's worth every penny. If you can't trust the data that the instrument provides, what's the use?