Attention new brewers, yes your original gravity reading is wrong. Don't panic.

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Revvy

Post Hoc Ergo Propter Hoc
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Hi, welcome.

You probably came here today because you just got your first kit, and you did what it said it all the books and all the forums, and you tried out your hydrometer for the very first time...and the reading makes no sense.

Yes it is important to get in the habit of using one, especially if you start brewing all grain. But when you start with extract brewing, like most of us did, the first reading can be a bit on the confusing side.

You didn't do anything wrong. In fact nothing's wrong at all.

We get this question 3-4 times every day, so you're not alone. And in reality, nothing's wrong.

It's a pretty common issue for ANYONE topping off with water in the fermenter (and that includes partial mashes, extract or all grain recipes) to have an error in reading the OG...In fact, it is actually nearly impossible to mix the wort and the top off water in a way to get an accurate OG reading...

Brewers get a low reading if they get more of the top off water than the wort, conversely they get a higher number if they grabbed more of the extract than the top off water in their sample.

RM-MN has a great analogy;

This phenomenon is easy to see if you have a glass measure cup, some dark honey, and water. Pour in half a cup of water into the glass container, then dribble in some honey. Notice the honey sinks right to the bottom? It's more dense because of the sugar it contains. Now use a toothpick to stir the water above the honey. This will simulate using a spoon in a 5 gallon container. Did you get the honey mixed in? Not likely. If you drop in some dry yeast, it will find the honey and begin eating and the activity of the yeast will mix the honey in just fine.

When I am doing an extract with grain recipe I make sure to stir for a minimum of 5 minutes (whipping up a froth to aerate as well) before I draw a grav sample and pitch my yeast....It really is an effort to integrate the wort with the top off water...This is a fairly common new brewer issue we get on here...unless you under or over topped off or the final volume for the kit was 5 gallons and you topped off to 5.5, then the issue, sorry to say, is "operator error"

More than likely your true OG is really what it's supposed to be. And it will mix itself fine during fermentation.

And just use the number it says in the instructions as the true OG, because it will be.

So the answer is, relax and do nothing.

Like 99% of everything else in brewing. Just relax, and everything will be fine.

:mug:
 
Nice work, Revvy. Was tempted to post one titled "Hey, new folks. Welcome to HBT. Now go check out the stickies" but didnt want to scare folks
 
Hey thanks for heads up Revvy, I've brewed a few batches now but my most recent was a simple Hefe and I came up way over the target OG. I was making a conscious effort to measure all my liquid amounts at various points (partly since I just picked up BrewSmith and wanted to dial in my boil off numbers). So I was having trouble figuring out the discrepancy. Anyhow this could very well explain the issue the only other explanation was the bulk LME I bought was misweighed (I didn't weigh it I just assumed the LHBS had it right) any somehow they gave me almost a pound extra LME.

One thing I did differently this time which likely added to this effect is to top off as opposed to having my water already in the bucket and adding wort to that, which I had done on my first couple of batches. So I wasn't particularly worried just confused, but I think this explains it pretty well.

So lesson for the future stir more once I add wort.
 
Hey Revvy, i get lazy and just put the hydrometer in the bucket for OG and in the keg for FG. Anyone else do that?
 
Hey Revvy, i get lazy and just put the hydrometer in the bucket for OG and in the keg for FG. Anyone else do that?

We're actually talking about the first gravity reading here before pitching yeast, it's one of the panic situations that brings a ton of new brewers here every day.

As to putting the hydrometer in the fermenter, if that works for you fine. But I would think that reading the meniscus is difficult enough in the test jar, and at least we can lift it up to eye level, looking down into a bucket seems like it would be difficult. Especially with krausen sticking to it.

Also, I tend to have 4-5 different things going at one time, like right now I have a Banana wine, a sweet potato mead, and honeycrisp hard cider, a red ale and a vienna lager going, each at various stages, I would need a bunch of hydrometers if I did what you did.

But like anything if it works for you, that's fine!
 
Hey thanks for heads up Revvy, I've brewed a few batches now but my most recent was a simple Hefe and I came up way over the target OG. I was making a conscious effort to measure all my liquid amounts at various points (partly since I just picked up BrewSmith and wanted to dial in my boil off numbers). So I was having trouble figuring out the discrepancy. Anyhow this could very well explain the issue the only other explanation was the bulk LME I bought was misweighed (I didn't weigh it I just assumed the LHBS had it right) any somehow they gave me almost a pound extra LME.

One thing I did differently this time which likely added to this effect is to top off as opposed to having my water already in the bucket and adding wort to that, which I had done on my first couple of batches. So I wasn't particularly worried just confused, but I think this explains it pretty well.

So lesson for the future stir more once I add wort.

One trick I've found is to stir the wort and water AND THEN use an oxygen stone/red bottle setup and oxygenate then take a reading. I find that the bubbling of it helps mix it further, it's probably the same with using and aquarium wand or some other oxygen supply method. Just stir and then oxygenate and then take a reading.
 
Quick question, what is the potential outcome of me failing to top off to 5 gal and only had 4.5 gal in a 5 gal batch? My OG was low, due to poor mixing most likely, but when I took my reading after 7 days it was at like 1.020. The starting gravity was supposed to be 1.058 but i came up with 1.042.
 
Way to be proactive! I got fooled my first 2 batches(at 6 now) till I read another thread on the subject. I think the biggest problem is that extract recipes(Brewers Best, at least) call for a partial boil of 2gals. Why not boil the full 5gals.? I assume its because they assume that,as a beginner, you dont have an adequate sized kettle to account for boil-overs?

Further research tells me that full boils are superior when extract brewing, and thus would eliminate the need for top-off, giving you an accurate OG, correct? I've also read posts mentioning negative issues with steeping specialty grains in a full boil. Is this an accurate concern? Hopefully I didnt derail the subject too much:eek:
 
This might be a stupid question, but when mixing it up afterwards could you use one of those mixers for speckle and a drill?
 
singram said:
Way to be proactive! I got fooled my first 2 batches(at 6 now) till I read another thread on the subject. I think the biggest problem is that extract recipes(Brewers Best, at least) call for a partial boil of 2gals. Why not boil the full 5gals.? I assume its because they assume that,as a beginner, you dont have an adequate sized kettle to account for boil-overs?

Further research tells me that full boils are superior when extract brewing, and thus would eliminate the need for top-off, giving you an accurate OG, correct? I've also read posts mentioning negative issues with steeping specialty grains in a full boil. Is this an accurate concern? Hopefully I didnt derail the subject too much:eek:

I have the same questions. I would much rather do a full boil.
 
Thanks, Rev, my first brew day was with a friend and he was confused by this very issue. A google search brought me here for the answer and I've been a lurker and contributor ever since. It's one of those first hurdles for everyone. Just remember, extract brewers, if your volume and amount of extract is correct, your OG should be spot on.
 
This might be a stupid question, but when mixing it up afterwards could you use one of those mixers for speckle and a drill?

You could, but I would not recommend it. You have no idea what may be on the drill or mixer, or what will surly land in the fermenter. I put the lid on and shake the heck out of it, after just dumping the wort in the bucket. Remove the lid and pitch the yeast on top of all the nice bubbles. Cheers:tank:
 
I consistently have this problem. For my last two batches I poured the cooled wort back and forth a half dozen times from one fermentation bucket to another from a pretty decent height in order to aerate and mix it. I have a really hard time understanding how the 3 post boil gallons weren't well mixed with the 2 additional gallons of cold water. There is a very substantial amount of foam created in the process, usually up to the top of the 6.5 gallon fermenters that I use. Could the foam be partially to blame for my measurement problems? I am using a wine thief to take my sample which means that it is coming from near the bottom, but for a 1.063 SG beer I measured 1.072 and for a 1.077 SG beer I measured 1.084. I'm sure the software is right, but I'm concerned that when I switch to AG or PM that I'll just have no idea what is going on.
 
I consistently have this problem. For my last two batches I poured the cooled wort back and forth a half dozen times from one fermentation bucket to another from a pretty decent height in order to aerate and mix it. I have a really hard time understanding how the 3 post boil gallons weren't well mixed with the 2 additional gallons of cold water. There is a very substantial amount of foam created in the process, usually up to the top of the 6.5 gallon fermenters that I use. Could the foam be partially to blame for my measurement problems? I am using a wine thief to take my sample which means that it is coming from near the bottom, but for a 1.063 SG beer I measured 1.072 and for a 1.077 SG beer I measured 1.084. I'm sure the software is right, but I'm concerned that when I switch to AG or PM that I'll just have no idea what is going on.

How sure are you that you have exactly 3 gallons of post-boil wort? If you had a higher boil off rate than you expected, you could end up with a higher gravity wort than your software expected. Also, have you calibrated your hydrometer?
 
So if you brew a full 5gals of wort do you need to worry about this. I know it is probably hard to do this with evaporation and what not, but to me the boil will help mix everything together. Just a thought, but yes great post!
 
Hey thanks for heads up Revvy, I've brewed a few batches now but my most recent was a simple Hefe and I came up way over the target OG. I was making a conscious effort to measure all my liquid amounts at various points (partly since I just picked up BrewSmith and wanted to dial in my boil off numbers). So I was having trouble figuring out the discrepancy. Anyhow this could very well explain the issue the only other explanation was the bulk LME I bought was misweighed (I didn't weigh it I just assumed the LHBS had it right) any somehow they gave me almost a pound extra LME.

One thing I did differently this time which likely added to this effect is to top off as opposed to having my water already in the bucket and adding wort to that, which I had done on my first couple of batches. So I wasn't particularly worried just confused, but I think this explains it pretty well.

So lesson for the future stir more once I add wort.

So I wanted to test exactly how much this could potentially effect my readings. The next beer I brewed I treated the same as I had with the hefe I topped off my concentrated postboil wort with water and stired a bit (about as much as I had been previously).

I took a reading from the top half with a thief and from the bottom via the bucket spigot. My expected OG was ~1.070 from the top I got 1.051 and from the bottom I got 1.090.

I mixed the batch again but this time vigorously and throughly, again took two readings. This time both gave the same reading 1.071 so leason learned mixing is very important if you want an acurate reading.

Of course I've now switched to full boils so for myself it might be a moot point.
 
How sure are you that you have exactly 3 gallons of post-boil wort? If you had a higher boil off rate than you expected, you could end up with a higher gravity wort than your software expected. Also, have you calibrated your hydrometer?
I have two True Brew 6.5 gallon buckets that are marked from 2 to 5 gallons at half gallon increments, so if the markings are good my measurements are good. The volumes certainly seem in the ballpark of what I would expect, but I haven't actually calibrated the buckets. I have calibrated my hydrometer, but it's certainly within a .001 as far as I can tell.

As I have said, I'm not so concerned now that I'm doing extract brews, but I anticipate doing a BIAB brew in the next month or so and don't have a refractometer or any expectations about what sort of efficiency I will get.

I'll try taking a top sample as well to see if it's a function of poor mixing or if my wort seems homogeneously out of whack.

Thanks,

Anthony
 
Was brewing for years then took off about 7 yrs and recently got back into it. Had very same issue and lhbs had me add more malt. Will back sure it ferments down but great post. Enough for me to sign up as a member. I like proactive people.
 
I ran into this problem last night while brewing my first Porter. It was my fifth brew, and first time i did not hit the correct range for OG. Recipe called for OG in the neighborhood of 1.050 and I got my initial reading of 1.072. It was extract with top off. I mixed it around for only like 1 minute then took my initial reading. I then aerated with O2 and took another reading. That was 1.068.

Its not a big deal because I am going to drink it anyways. My only real question is how will i know what the alcohol content will be? Should I just assume the OG is around 1.050? Or should I drink 4-6 bottles when it is ready and try to judge how big my headache is the next day?
 
Ifit's extract with grain, and your volume is correct, the ACTUAL og is what it should be. It can't be anything other with extracts. You are not converting anything.
 
It's not impossible at all. I've done three kits so far and every one had an OG that was right on the money.
 
I pretty much always assume that no matter what my OG reading is, its pretty damn close to whatever the recipe called for. From my understanding, its pretty hard to miss the OG by much with an extract recipe.
 
I've been moving towards full boils (maxing out with 5 gallons to start the boil, then topping off with about a gallon of spring water to make up for the loss to steeping grains and boil-off), and I've been finding it easiest to just measure the OG pre-topoff, and adjust the reading to my dilution factor.
 
Thanks for the responses. I now understand that it is pretty hard to mess up the extract numbers because there is no conversion, as Revvy stated. And full boil is one of the goals, but getting a fermentation chamber setup is first. (hopefully this weekend).
 
It's not impossible at all. I've done three kits so far and every one had an OG that was right on the money.

That's also been my experience for years.
I'd be real interested to watch exactly what people are doing that make the reading so far off.
Youtube maybe?
 
I've been stirring (as many as 200 stirs) and still get a slightly high reading - about .003 - .004 off. I could stir longer, but I don't see any real advantage. Is there anything wrong with just using the kit specified gravity? I've already aerated, so I was thinking of backing off to 100 stirs and accepting an even greater discrepancy. The sooner the fermenter is covered and sealed, the better I like it.
 
I've been stirring (as many as 200 stirs) and still get a slightly high reading - about .003 - .004 off. I could stir longer, but I don't see any real advantage. Is there anything wrong with just using the kit specified gravity? I've already aerated, so I was thinking of backing off to 100 stirs and accepting an even greater discrepancy. The sooner the fermenter is covered and sealed, the better I like it.

There's nothing wrong at all with just using the kit gravity for an extract batch. Fermentation will mix water and wort together just fine.
 
gcdowd said:
When I did extract batches, I never bothered to take an OG reading.

I'm with you...mine have all been off...but the fg's have been just about right on. Why waist the brew.
 
Theres been alot of "OMG I MISSED MY OG" posts this weekend so I'm bumping this.
 
Revvy got it all wrong. The correct response should be to: "continue the process best you can till the end and bottle it. Once the hazardous and defective product is properly bottled, I will be glad to dispose of this hazardous waste for a nominal fee plus expenses. Fortunately for you, I am certified and trained in this field and can handle these problems."
 
Oh I've got 14 cases of used bottles for sale, cheap! Soon to be 16. The IPA I am disposing of now took a while to clean up. But its finished nicely after extended conditioning in the bottles so I'll be inviting friends over on my days off, and those bottles should be available by week's end...
 
It's funny how we sometimes can get lost in the small details. It is always reassuring to read some words of wisdom for those who have a heck of a lot more experience. Glad this post got bumped up.
 
I have a question about they hydro. Sunday I brewed 9.9lbs golden light extract IPA with 2 lbs of steeped grains. According to beersmith I should have had close to 1.07 and I got 1.046. It was a full boil extract for 60 mins with some burnt sugar on the bottom of the keg. Anyhow I am curious as to the reading I took. When filling the test tube I took enough wort to barely float the hydro and not much more. A friend suggested that perhaps it didn't have enough liquid to make it buoyant enough to reach the full SG. Any one else do or witness this and then fill it further? I didn't pull a second sample to verify and just trusted what it said the first time.. silly me.
 

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