Do I have a magical refractometer, or can anyone float a hypothesis why everyone else's refractometers need continuous recalibrating?
My Marine Depot refractometer from ~2005 is still basically on its original calibration.* Reads RODI correctly, reads calibration fluid (American marine and Brightwell) correctly. All I've done is use it and put it back in the case (dry) when done. It does not change on its own or "from usage".
Am I babying it??? Are they just not making them "like they used to"? I'd be back to using a hydrometer if my refractometer acted like that.
* It did get purposefully miscalibrated, then recalibrated once about 10 years ago.