Not all refractometers are alike. I really love my VeeGees and keep two around. Some should be calibrated with reference solution while others should be calibrated with RODI (like my VeeGee). Confirm that.ok. That means both my salinity measuring tools are testing low after calibration. Which is annoying, but good to know.
I thought some of the trace elements were important?
The test had to go to Poland. Had I known that before buying the tests I would have gone for something else. I know for next time.
IF you are doing water changes, you should be OK on traces. What mix are you using?