I had the same problem I have a cheep refractometer and it never matches hanna checker. I go with the hanna because it matches closely to one of those cheep float checkers. Take your hanna checker to the lfs to see what it says.What got me to get a refractometer was I took a small cup of my tank water a week ago to one of the LFS here (not my main go to) and read a high salinity through a refractometer that I thought possibly may have been an error (or that my sample had some evap since it was like 100ml although had a lid).
Could both Hanna pouches of calibration fluid be a bad batch that I calibrated both my Apex probe and Hanna checker to? I floated them in my 78° tank water before calibrating.
Worst case if I come to find out my tank is at 42ppt, how fast should I lower? 1ppt a day?
I’m going to bring another sample to get tested at my main LFS and also bring both salinity testers to find out tomorrow.