Hydrometer – detailed instructions
Sunday, January 30th, 2011 at
7:32 pm
This is a very detailed video showing how to use a hydrometer for home brewing beer and wine. ABV calculator:
Tagged with: detailed • hydrometer • instructions
Filed under: Beer Making Supplies • Beer Supplies
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@blitzkriegstaffords, thanks for the info about the formula!
Oh, Craig, you are mighty terrific. You got me onto inmate brew and now I am in love not only with the finished product but the entire process. Thanks, my friend. Your videos are always a pleasure
thanks brother! very informative vid on something that i was not totally clear on. keep up the good work.
Thank you, thank you, thank you. I’ve avoided using the hydrometer until now. I’l be using it tonight.
depending on the style of beer you are brewing 1.040 can be very low. kybourbon, to figure out the % of your alcohol content you take your (OG-FG) x 131.25 = alcohol %
Craig, this is the perfect Hydrometer video. I make wine right now and haven’t used one, though now I am so curious and wish I had! I will make sure to purchase and use one in the future though.
@kybourbon1 There are formulas, but the easiest way is to find an ABV calculator online and plug in your numbers.
@CraigTube, o.k. now what? you got your O.G. & F.G. readings how do you use these numbers to determine your % of alcohol. do you subtract one from the other or is their a special formula. you never explained, you just showed us how to read a hydrometer. not how to figure alcohol content. it was still a good video.
@missextreme28
I have the same question actually.
Your a champion Craig. This is really informative as are your other videos. I’m a subscriber now. Thanks mate from downunder
Has anyone got any readings for when to stop/start cider???
I have a question, Now in my 6.5gal carboy I have fermenting Coopers Draught. It makes 6 us gallons of beer, after carefully mesuring the water, and dme, i poured my wort in the carboy and it is showing around 6.5 gal of liquid. And I only started with 5 gal of water in the carboy and used 1/2 gallon to boil my ingredients. Is it ok that its a bit over the 6gal mark?
I tasted a sample, and it tastes fine, with a sg of 1.043. Any ideas? Cheers!
thanks very helpfull
Nice, Thanks Craig. I lost my calculator and the link was just what I needed..my son tells me that “curve” on the reading is called a “meniscus” . I know, surprised me too!
Nice, Thanks Craig. I lost my calculator and the link was just what I needed..
thanks for the post
Cracking vid Craig, informative and accurate, and well presented.
Absolutely love the 2nd blooper when you turned round to the table!
I daren’t admit to how many times I replayed that bit!
@segontium I’m not having any issues with a plastic taste. Food grade containers should be just fine.
ooooah, thanks Craig for sharing your knowledge with us, really informative with fun.
I hope to start brewing in the near future.
I last brewed about 25 years ago and I much preferred to use glass bottles bcause I found that the barrel that I used added a plastic taste to the beer.
Are todays barrels any better in that respect ?
Diolch yn fawr, thanks a lot, from Wales.
Thanks Craig, I didn’t know what the heck to do with it until I saw a quarter of your vid.
i have just started wit home brew love the vids u do make it look simple … cause it is lol wish u had a vid for priming bottles and head of the beer.
@TheMarks82 OG of 1056 is fine. Usually the more sugar/malt etc you put in the higher the OG. I jsut did a batch of IPA with OG 1058 and airlock wasnt moving. It fermented fine however. Some are very slow. You can usually see the faomy ring around top of your brew in fermenter and take the SG and see. if its 1012-1010 or so its ok. Leave it 2 days. If it reads same SG as 2 days ago its stopped and its good to bottle.
Hi Craig,
This is my first time brewing beer. As part of my kit, i received a hydrometer, but it doesn’t have that scale as a normal hydrometer. It has a reading from 0 to 20.My fermentation stopped on the third day, and now on the fourth everything looks just fine, with the “hydrometer” pointing at 4. what does this mean?
Hi Craig,
This is my first time brewing beer. As part of my kit, i received a hydrometer, but it doesn’t have that scale as a normal hydrometer. It has a reading from 0 to 20.My fermentation stopped on the third day, and now on the fourth everything looks just fine, with the “hydrometer” pointing at 4. what does this mean?
craig, where where you when i was at school?, i might of actually learnt something,
@BobbyFromNJ Thanks for your reply, it was after fermentation. It was brewed by someone else so i dont know the OG… I was looking around since and because there was no reading taken before fermentation you cant know for sure what the ABV is without sending it to a lab.
@nodnodwinkwinkV
What this measured before fermentation or after? If it was after, you really have to know where it started to calculate ABV.
Heres a random question for you, i tested a homebrew cider for alcohol content with a hydrometer that came with a coopers hombrew starter pack. The result that came back was 1.020. This gives 2.84% alc. volume.
This was from nothing else that fermented apples, no sugar, no yeast etc.
Could this be correct?
@Markohoppis Look up specific gravity.
Much appreciated!
For any Mac users BeerAlchemy is a great tool.
This was really clear and concise especially for a beginner. EXCELLENT job. Thanks for taking the time to explain.
hey great vid , exactly what i was looking for, do you have any tips for bottle priming?
Thanks
Eoin
thanks for mentioning beertools
Thanks for the info on the hydrometer. I found some hydrometers and test jars at good prices on AlcoholControls. com in the liquor controls section.
@BobbyFromNJ Thanks for the reply. I found a few different ways for calculating ABV. I read that hops do not interfere with the specific gravity reading.
@Markohoppis
SG is a measure of how much heavier a liquid is than its pure water counterpart. 1.051 is 5.1% heavier than water.
A pound of table sugar in a gallon of water would yield 1.046.
1.051. What does this number mean? That there are 2 pounds of sugar in 1 gallon of water?
I know how do the math, but don’t understand the theory behind it.
Thanks for this video. My friend and I are just getting into the wine making hobby and this helps big time with this tool. Thanks again.
Well done. I been reading up for dayss now and just the few videos of your that ifv seen sofar have hepled put to getther some of that Data in my head.
by the way kudos on the video, good subject great rule of thumb and abv conversion.
BobbyFromNJ another good beginner topic would be; how long to let wort ferment in primary secondary, after priming and bottleing for different styles at least hitting the major styles and possibly touching base on how long to condition for lower 3.5 to 5.0 abv versus brews with higher 5.0 to 6.5 abv. thanks
u don’t use a hydrometer for beer & wine, to test vodka or other high alcohol spirits, it’s not made for that. u need a hydrometer that’s made just for high proof spirits. Their two different things. Hope this helped the confusion!
First video ive watched from you. Very good topic for it is the most confusing and less talked about in beginner videos. This cleared up those final questions i had before i try my first pot
thanks
hello i am new to the beer makeing lol wen shud a test my hydrometer ?
A couple more comments….
Spirits like vodka are 40% ABV give or take and the rest is water. So, you can imagine typical brewing hydrometers wouldn’t even register because they are well under “1″ on the gravity scale. Vodka has no sugar in it because it’s left behind during distillation.
While the alcohol is increasing, and is less dense than water, there is still quite a bit of residual sugar left by the time the yeast pack up and go home. We are not making pure ethanol here. Typical session beers stop at about 1.010 which represents a balance between the pure ethanol, the water, and the residual unfermentable sugars which increases the density to whatever the FG is.
Go ahead and test the gravity of your favorite barleywine or RIS, but make sure you let it go flat first.
Thanks for the reply. Ok, I’m very confused. The reason a hydrometer sinks further and further into the liquid is beacuse the alcohol content is getting higher and higher. Try droping a hydrometer into vodka, it just goes straight under and hits the bottom. With that in mind, how could a beer with higher ABV say 10% have the hydrometer poking further out of the liquid at 1.027 than a beer with a ABV of 5% – 1.010?
That what I find hard to understand.
Pete
urainusishere, sorry, I don’t agree. Dividing OG by 4 is a perfectly good rule of thumb (for a beginner) to predict FG. It’s based on a typical apparent attenuation of 75%. A beer with an OG of 1.110 will absolutely finish up somewhere around 1.027 although with an ABV of about 11%. Have you actually made any beers with an 1.110 OG? What was your FG then? I’ve done three beers over 1.100 so far and they all end near 1.030 give or take.
With respect to you Bobby, your calculations to predict the FG from the OG are wrong.
The higher the OG number the lower the hydrometer will drop into the liquid due to the low density of the liquid. For eg,, An OG of 1.110 OG (about 15% final) would have the hydrometer almost fully submerged due to the high alcohol content (lack of density). Not the 1027 reading you would arrive at with your calculations, (1.110 divide by 4).
Pete
thanks much, Cheers !