I suck at hydrometer readings

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JollyMon

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I am new to using a hydrometer (never bothered with MB kits). And I have to say that I really suck at it. Can anyone provide any tips to a noob. It seems like every time I look at the damn thing it reads something different, or there are bubbles in the way, or something else is keeping me from feeling confident in my readings. I could use some help.
 
A trick I use when there's too many bubbles... note that I use a cylinder vessel to take readings from. I grab a flashlight and shine through the beer at an upwards angle at the hydrometer. This way you can read from the bottom UP to the surface of the liquid and get an accurate reading this way instead of dealing with bubbles in your way.
 
For one thing, make sure there is no foam on top before you put the hydro in. If there is use a paper towel or something to get it out of there so you can read it. Wait for it to stop bouncing up and down before taking the reading. Also, if the sample is hot, cool it down before taking the reading. The closer it is to the calibration temp of the hydro the better. They have charts for temp correction but they are unreliable.
 
I broke mine and ended up buying a cheap refractometer on ebay -- about $30. Way easier and you only need a few drops instead of several ounces.
 
bk0 said:
I broke mine and ended up buying a cheap refractometer on ebay -- about $30. Way easier and you only need a few drops instead of several ounces.

Refractometers are cool but I can hardly taste those tiny samples...
 
Trick I learned working at a brewery:

1) Fill up your sample tube farther than you would

2) Place sample tube in sink or other place you don't mind getting beer

3) Slowly lower hydrometer into tube, allowing beer to spill over the top of the tube (there, no bubbles!!!)

4) Give the hydrometer a healthy spin. This will knock out any bubbles that might be clinging to the hydrometer (and possibly throwing off the reading)

5) Note where the meniscus is on the hydrometer. The meniscus is the curve a liquid makes in a cylinder due to surface tension.

6) How to read the meniscus properly:
Reading_the_meniscus.png


When your sample is in the tube the meniscus will look like it does in A. However, once you add your hydrometer, the meniscus will creep up the side of your hydrometer. The correct reading will be as such:
hydrometer_read.gif
 
^ Good explanation.


It has been touched on already but it is imperative that you get yourself a hydrometer test tube to get accurate readings. Seems a lot of new brewers just try to stick the hydrometer in the fermenter...that won't work!

You need one of these:

42-Dropping-hydrometer.jpg
 
Thanks for the pictorial explanation reno. I have such a hard time explaining to folks that you read through the base of the meniscus. Not at the top of it. Some insist that the instructions say to read at the top. But I know from science/living sciences classes that that's wrong. Or maybe they have a hard time using imaginary line of sight.
Just gotta go snake eyed...& at least use the tube the hydrometer came in to take the sample.
 
Thanks for the pictorial explanation reno. I have such a hard time explaining to folks that you read through the base of the meniscus. Not at the top of it. Some insist that the instructions say to read at the top. But I know from science/living sciences classes that that's wrong. Or maybe they have a hard time using imaginary line of sight.
Just gotta go snake eyed...& at least use the tube the hydrometer came in to take the sample.

My old hydro said "read @ top of meniscus". Then I broke it. New one says "read below meniscus".

Pretty sure there's a difference. No? :drunk:
 
I was just thinking that maybe the hydrometer was set up that way. Or the manufacturer had it wrong? Maybe just the way that one was set up to make it easier to read?...
 
Everyone of us should be calibrating our hydrometers in distilled water so you know where you are supposed to read it.
 
Well,every hydrometer I've ever used since jr high was read through the base of the meniscus. It threw me when some said otherwise. Never heard of or saw that before.
 
Some great responses here. Thanks everyone. I am sure that it will get easier in time, but in the mean time these suggestions are sure to be helpful.
 
unionrdr said:
Well,every hydrometer I've ever used since jr high was read through the base of the meniscus. It threw me when some said otherwise. Never heard of or saw that before.

Same for me.



And +1 to calibrating in temperature-appropriate (see hydrometer, it's most likely 60°F) distilled water.
 
I broke mine and ended up buying a cheap refractometer on ebay -- about $30. Way easier and you only need a few drops instead of several ounces.

refractometers are great and I love mine for pre-boil, post boil, etc, but not so much for final gravities - too much correction math for the alcohol.
 
Reno_eNVy said:
And +1 to calibrating in temperature-appropriate (see hydrometer, it's most likely 60°F) distilled water.

When I calibrated my hydrometer I used the same water, same temp that I use for my brewing: 65F filtered tap water. It read .998 so I just add .002 to all my readings. Should thus be pretty accurate?
 
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