you also need to adjust the refractometer based on temperature. Easiest way is to take the sample and then let it sit and cool and use your ambient temp and online calculators. also gotta be careful of what scale they use when you buy one. I think you can get them with SG on them as well as brix, sadly no one makes one for plato(that i have found yet). Also try to get one that has a smaller range because it will be more accurate and easier to read. Mine goes from 0-18 Brix i think.
They make unbreakable Hydrometers, but they are pricey and dont have temp calibration like the glass ones do.
For me temp calibration is pretty important, but this is not really a hobby for me... temp can make a pretty big difference in the actual reading.
These are the type that I have always used in commercial settings. Pricey, but accurate. I keep a 0-8, 8-16, and 16-24 plato set on hand.
https://www.amazon.com/SafetyBlue-ThermoHydrometer-Thermometer-Traceable-Certificate/dp/B00YYMG5EU/ref=sr_1_1_sspa?crid=31K11458WFWMU&keywords=hydrometer+plato&qid=1698428606&sprefix=hydrometer+plato,aps,116&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1
This is the Refract that I currently have(in a different scale). It is good, but i rarely use a refract.
https://www.amazon.com/Refractometer(Teflon-Automatic-Temperature-Compensation-Refractometer/dp/B07BN9RGGK/ref=sr_1_22_sspa?crid=1RD2BNYIZSTOW&keywords=hydrometer+plato+plastic&qid=1698428741&sprefix=hydrometer+plato+plastic,aps,117&sr=8-22-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9idGY&psc=1
Shatterproof hydrometer, but not temp calibrating. This one is pricey but maybe its cheaper if you end up breaking them every time you use them!
https://www.coleparmer.com/i/cole-p...414JnzPCjSXmqizDFVy1Gc_U04eJ4YYRoCvMQQAvD_BwE