How often should I take hydrometer readings?

[brewsers]

Hello all

I and one of my buddies just got into brewing and we have had our wort in the second fermentor for about 2 weeks were about 2.7% we think - my real question though is how often should be taking hydrometer readings?

 

[ciphin78]

I take one reading right before pitching (to see if i've hit my OG) and then once about 3-4 weeks later right before kegging/bottling to see if i've hit my FG. I view taking readings as just another opportunity to introduce bad things into your beer so the fewer times I have to take a reading the better. Just my two cents.

 

[Hang Glider]

There is no value to an "intermediary" reading -

Starting or Original gravity, and Final Gravity - that's about it.

so, I am in full agreement with ciphin78 - just before pitching, and 4 weeks later.
It is a tool to help determine final alcohol, but also to see if you've got a stuck fermentation. If I read 1.054 at OG, and 1.032 at Final, I would know I had a problem.

 

[BrewKnurd]

You should take a gravity reading whenever you might actually do something based on it. For most people, this just means before and after fermentation.

I believe I heard Tasty McDole say on a BN podcast that he likes to dry hop when about 10% of fermentation is remaining. Without making any judgement on whether that's the best time do dry hop or not, since that's an entirely different topic... if that's your goal, to dry hop with 10% of fermentation remaining, you obviously have to measure your gravity throughout the ferment to identify when you have 10% left.

But if there's nothing you're going to change or do based on the reading, you would be better off not taking it.

 

[ciphin78]

But if there's nothing you're going to change or do based on the reading, you would be better off not taking it.

I'm assuming your statement means if your not going to do anything...ever...don't bother. Otherwise, It's important even if you can't do anything for that specific batch. It can help in future batches for perfecting your process and troubleshooting issues. If that's what you meant (and I think it is), I concur.

 

[BrewKnurd]

I'm assuming your statement means if your not going to do anything...ever...don't bother. Otherwise, It's important even if you can't do anything for that specific batch. It can help in future batches for perfecting your process and troubleshooting issues. If that's what you meant (and I think it is), I concur.

Yeah, that's pretty much what I mean. :-D I'm operating under the assumption that everyone is going to be taking original and final gravity measurements, even though there may be nothing they can do about it for that batch, because as you say, its important info to understand your efficiency, fermentability of your wort, yadda yadda.

I was mainly saying that if the only reason you're taking a reading after two days is because you're curious about how far its attenuated, but you're going to let it sit another 2 weeks regardless, I would argue that's nothing but increasing your risk of contamination or oxidation.

 

[beergolf]

about 2.7% we think

How are you getting that %? The % scale on the hydrometer is not for brewing.

Calculating ABV is easy. Use this formula. (OG-FG) X 131= ABV.

 

[jaycount]

As stated above, I take a reading when it goes into the fermenter then I take a reading after about 2-3 weeks to make sure I'm at terminal gravity (assuming this is a low-medium gravity batch). Then it goes to secondary if it needs it (fruit, dry hops, oak) or just waits in the primary until I have a keg that's ready.

 

[licenseless]

unless you are worried about the process in which your beer is going threw... i wouldnt worry about taking more than two readings...

an OG and an FG

i honestly havent taken an OG in my last few beers simply because i can tell by taste of my wart or mash if i am were i need to be... depending on the weight of the grains...

i usually only take an FG to make sure that i can keg the beer and it doesnt have to much sugars in it to become over carbonated...

if i am down around 1.14... or so... then i can bottle or keg... if not... then figure out whats going on... or get more patients

 

[brewsers]

How are you getting that %? The % scale on the hydrometer is not for brewing.

Calculating ABV is easy. Use this formula. (OG-FG) X 131= ABV.

OG ? Old gravity? Fg? Sorry I am pretty new to brewing

 

[eltorrente]

OG ? Old gravity? Fg? Sorry I am pretty new to brewing

OG - original gravity
FG - final gravity

You might want to pick up a beginners book. This stuff is important, basic knowledge (don't mean to sound condescending - sorry).

 

[BrewKnurd]

You might want to pick up a beginners book.

Yah. At the very least, give http://howtobrew.com/ a read. its an online copy of the first edition of John Palmer's very good intro to brewing book. Just ignore what he says about secondarying most ales, he doesn't believe that is good advice anymore. So best option would be to buy the latest edition of the book, but if that doesn't work for you, at least check out the free version online.

 

[Dunkelman]

Okay, new brewer here looking for clarification. It seems the concensus here is two readings, OG and FG. in other posts, however, I read how you know the fermentation is complete when you have a SG that doesn't change for three consecutive days. This seems to fly in the face of what everyone is saying on this thread, because wouldn't you have to take a hydrometer reading each of those three days to determine the SG?

 

[Kealia]

Some do. Every brewer is different and IMO this isn't a situation where there is a "right" answer, it's Brewer's Choice (tm).

I take an OG reading of course, then I take another reading after 10-14 days depending on my schedule, if I forget, etc. At that point, I know if I'm close to my target FG, way off (maybe indicating a stuck fermentation), etc.

I then save the sample in a satellite fermenter (fodder for another discussion) and check that again in 1-2 days to see if I've hit terminal gravity.

Ultimately, it's going to be up to you but hopefully all of the options out there give you some ideas.

 

[BrewKnurd]

Okay, new brewer here looking for clarification. It seems the concensus here is two readings, OG and FG. in other posts, however, I read how you know the fermentation is complete when you have a SG that doesn't change for three consecutive days. This seems to fly in the face of what everyone is saying on this thread, because wouldn't you have to take a hydrometer reading each of those three days to determine the SG?

1) you really don't need to take three measurements on those three days. You can just take a measurement on the first and the last of the three consecutive days.

2) I would argue that any measurements you take while confirming F.G. are really F.G. readings. So even if you're taking multiple readings, you're still just measuring F.G. Unless you find that you're not, because it is indeed still dropping.

 

[brewsers]

Sweet - thanks for all the tips it will definitely hep me out!

 

[completenewbie]

I'm lazy, and an extract brewer (doubly lazy!) - I tend to leave every brew for a month, and then take a reading - I have serious issues getting anything below 0.018, so as long as the beer is down to around 1.020 I bottle it. After a month, nothing new is going to happen. The only issue I had was a milk stout which ended up at .030, which bottled fine.

 

[bomberman]

I usually take one pre-pitch and one right before bottling/secondary. Give it enough time and the right temperatures and there is no need to confirm that fermentation is complete as long as you're close to your target FG.

 

[Rev2010]

I read how you know the fermentation is complete when you have a SG that doesn't change for three consecutive days. This seems to fly in the face of what everyone is saying on this thread

Keep in mind most of us use some form of brewing software that gives you the estimated OG and FG. I use Beersmith and it is damn accurate! I am always no more than .002 off of either reading. In other words, my estimated OG may be 1.054 according to Beersmith and I'll get 1.053 and at the worst 1.052 - though it's very rare I'm ever .002 off, I'm usually within the .001 area.

So, when the software says your FG is estimated at 1.013 and when taking a hydrometer reading I get 1.013 or 1.014 I know it's done. No need to do the wait 3 days and try again. Brewing software is extremely helpful and a very useful tool.


Rev.

 

[BOBrob]

OG ;original gravity- your fist reading before fermentation begins(around 1.055?) and FG ;final gravity is the reading when fermentation is stable ( around1.010 ?) . You will also see references to John Palmers brew book . Its free on line and a must read for all brewers. Cheers and welcome aboard

 

[brewsers]

Keep in mind most of us use some form of brewing software that gives you the estimated OG and FG. I use Beersmith and it is damn accurate! I am always no more than .002 off of either reading. In other words, my estimated OG may be 1.054 according to Beersmith and I'll get 1.053 and at the worst 1.052 - though it's very rare I'm ever .002 off, I'm usually within the .001 area.

So, when the software says your FG is estimated at 1.013 and when taking a hydrometer reading I get 1.013 or 1.014 I know it's done. No need to do the wait 3 days and try again. Brewing software is extremely helpful and a very useful tool.

Rev.

How do you use beer smith to do your calculations?

 

[Rev2010]

You input your recipe and it does all the numbers.


Rev.

 

[Dunkelman]

Thanks all for the clarification. Makes complete sense.

 

[TearlessWyvern]

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