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Stupid question of the day Refractometer vs. Hydrometer

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GJOCONNELL

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Just to make sure I am not going crazy.

I used the refrac. post boil after being chilled down to 70 f then take a sample and see what the measurement is.

I use hydrometer after pitching yeast and letting the wort sit for a couple weeks at the desired temp (usually 68 f for my brews but I know this can vary depending on the receipe). I check using the hydrometer a couple times to ensure the FG is consistently at a lower level than the OG.

Am I doing this correctly?
 
Just to make sure I am not going crazy.

I used the refrac. post boil after being chilled down to 70 f then take a sample and see what the measurement is.

I use hydrometer after pitching yeast and letting the wort sit for a couple weeks at the desired temp (usually 68 f for my brews but I know this can vary depending on the receipe). I check using the hydrometer a couple times to ensure the FG is consistently at a lower level than the OG.

Am I doing this correctly?


More or less, but just ensuring that your FG is lower than OG isn't enough to be sure your beer is done fermenting.

You should have an expected FG number for your recipe. I would recommend using an online brewing calculator or recipe builder which will estimate your OG and FG based on ingredient and yeast choices. This will give you something to compare your readings to.

You also want to make sure your FG reading is the same both times you check it. If it is still dropping, your beer is still fermenting.
 
Just to make sure I am not going crazy.

I used the refrac. post boil after being chilled down to 70 f then take a sample and see what the measurement is.

I use hydrometer after pitching yeast and letting the wort sit for a couple weeks at the desired temp (usually 68 f for my brews but I know this can vary depending on the receipe). I check using the hydrometer a couple times to ensure the FG is consistently at a lower level than the OG.

Am I doing this correctly?

You are using the equipment correctly; refractometers are pretty much temperature independent, but alcohol will throw them off and hydrometers are temperature dependent and not effected by the presence of alcohol.

There are ways around this. You can correct for either instrument with some calculations.
 
More or less, but just ensuring that your FG is lower than OG isn't enough to be sure your beer is done fermenting.

You should have an expected FG number for your recipe. I would recommend using an online brewing calculator or recipe builder which will estimate your OG and FG based on ingredient and yeast choices. This will give you something to compare your readings to.

You also want to make sure your FG reading is the same both times you check it. If it is still dropping, your beer is still fermenting.

I use Beersmith and yes I check several times to ensure the FG is the same and near the target FG.....
 
I use Beersmith and yes I check several times to ensure the FG is the same and near the target FG.....

Then yep, you are using it correctly.

You can also check your refractometer readings before cooling down. Since you are only using a couple drops of liquid they cool to ambient temperature in a few seconds. This is useful if you are boiling to a specific gravity rather than for a time.
 
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