Recently I had my Hanna tester go bad, it wouldn’t hold calibration and was reading my tank as 1.024 and LFS tested it at 1.030. That’s how I found out cause I suspected something was wrong because I would add salt but kept reading 1.024. (It’s a nano tank before people say I’m stupid for continually adding salt, doesn’t take much in a 5 gallon) Hanna sent me a new one. I also ordered the Milwaukee MA887 brand new cause I didn’t want to use Hanna anymore and out of the box it read its own calibration fluid of 1.025 as 1.028. I tried like 10-15 times recalibrating and testing my water, using their samples, my own RODI water and DT water, even tried to test the Hanna calibration fluid that is supposed to be 1.026 and it read it as 1.018? I then ordered the Veegee STX-3 and it just got here and if I calibrate it to 1.000 using my RODI water it reads my tanks at 1.028. My replacement Hanna is here too and it reads my tank at 1.025. Someone please tell me what to do lol, I have all these testers and none of them even slightly resemble the other. Is there a place I can pay to ship my water to be tested to know 100% where it’s at? Then calibrate the Veegee to match?