65Chev: I'm not sure how familiar you are with a refractometer. Once the fermentation process begins, the refractometer is not going to accurately read the correct gravity. The presence of alcohol that's been created by the yeast will "skew" the reading. During brewing, before the yeast is pitched, the refractometer is spot on if calibrated.
There's a work around, and it requres some math OR it requires a free spreadsheet program that you can download on Morebeer. Also, most brewing software has a refractometer calculation.
BobbyM has a You Tube video that explains this entire process, it's well done. You plug in your starting gravity, and when you take additional samples as the fermentation progresses the software correctly calculates the correct gravity from the Brix reading.
What I do is take a straight racking cane that's sanitized and place the end down into the beer, with draw a small sample and place it onto the lens of the refractometer, record the reading, and enter that Brix reading into the spreadsheet.
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