Meniscus & ABV calculation

[Robsparky99]

I'm confused!? (happens easily)
I got a strip torn off me the other day, when my wife looked at the hydrometer reading when I was taking my OG. She said that you have to take the reading at the middle/base of the fluid, not the raised edge (Like I have been doing since I started).
Technically in chemistry she is right (I guessed she would be, because she works in a Lab!), but I have seen that some hydrometers tell you to take form the raised edge...Can't find anything out about the Coopers Hydrometer which I use all the time. I'ts only about 1-2 points out, but what do people usually do?

Also the ABV calculation is the Coopers method, is that the best to use?

 

[terrym]

Your wife is probably right. But if you are unsure dunk your hydrometer in clean water at the calibration temperature which should be marked on it somewhere (usually 20*C) and it should read 1.000 and take it from there.
Try this for ABV
https://www.brewersfriend.com/abv-calculator/

 

[kelper]

I would put it in water and see where 1.000 is in relation to the meniscus. For most hydrometers, the reading is taken at the bottom of the meniscus, but on my French 'Alla' the instructions say to read above the meniscus. Is yours plastic? https://www.mantality.co.za/plastic-hydrometer.html

I'll gladly send you a photo of the instructions if you are brave enough to win an argument with your wife!

 

[jceg316]

I don't think it matters too much, as long as both the OG and FG are read in the same place. On my hydrometer the difference is 0.001 between the top and bottom of the meniscus, I get the same ABV for either but tend to read the bottom.

 

[foxbat]

Your wife's right.

This is generally the rule to apply for a happy life.