I bought a agricultural solutions refractometer when I first started my tank. I struggle to read the numbers on it and have found it to be inaccurate. I went ahead and bought a hanna salinity tester thinking it would be easier to use but I find myself constantly needing to calibrate the thing. I am running through the calibration solution. i'm on my second order from BRS in only a few months. My question is... is there a refractometer out there that's reasonably priced and accurate? What are you guys using? I'm not really trying to spend more than a couple hundred dollars here. I will spend a little more to insure accuracy. Thanks in advance for your help.