Hydrometers

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ReaperOnefour

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Hello all. I'm looking to buy my first hydrometer. I brew one gallon batches. I'm not to worried about taking a sample for my OG, because I can always add more water to the wort. My concern is taking a sample for my FG. I don't want to lose that much beer. I've read somewhere that if you sanitize the test jar, you can put the sample back. Is that true?
 
Get a refractometer and maybe a FG hydrometer. The first will be good for both but you need to do some calculations to determine FG bc alcohol changes the reading. I won't get into the details but it's worth it.
 
Or sanitize the hydrometer and put it directly into the beer. Probably a little less oxidation will occur that way too as you aren't pulling a sample and dumping it back in, just gently putting a hydrometer into the fermenter.
 
^ you have never broken a hydrometer or a floating thermometer inside the kettle or anything have you?

I would higher recommend against this unless you have never broken a single glass in your life.

Just realize that you will loose the beer and add more volume this way. You really should have a feel for the end of fermentation and only do two measurements
 
I can't even gently put a hydrometer in my sample tube.
I once broke a hydrometer and glass tube simultaneously.

My LHBS closed down. I bought 3 spares. Thought I broke one before I got home.
No way in hell I'm putting one in the bulk of my beer/wort.
What was the OPs question?
 
About putting the test back into the beer. I wouldn't risk the infection but in theory yes he is correct. Many things can go wrong...
 
Or sanitize the hydrometer and put it directly into the beer. Probably a little less oxidation will occur that way too as you aren't pulling a sample and dumping it back in, just gently putting a hydrometer into the fermenter.

How are you going to read it? Usually krausen cakes the sides of the fermenter. And you need to read it at eye level.

Dumping back a hydrometer sample seems unnecessary for maybe 4 ounces.
 
With one gallon batches I would just trust the beer gods to keep me from making bottle bombs. Pitch healty yeast, if dry - rehydrated, and give it enough time to fully ferment.

NO Gravity measurements at all.....

If you must, I would sanitize well and return the sample. Either that or increase you batch size to account for gravity samples.
 
Thanks guys for all the great tips. I was actually looking into refractometers as well. I saw that northern Brewer has that online calculater that will tell you the FG. I think it tells you the PA too. The refractometers are more expensive too though.
 
For small batches, like yours, a refractometer only makes sense. The results, using the gravity correction calculator, can be as good as a hydrometer.

FWIW, measuring FG is only important as an indication of gravity stability, the yeast having done their job. If it comes in higher or lower than expected, there is usually not all that much you can do about it.

I bought my refractometer off eBay from one of the larger sellers from the North West. It's the "heavy duty" version "weighing 25% more" than the "economy" model, and surely doesn't feel flimsy. It was around $23 shipped, 4 years ago. It's supposed to have a corrected OG scale, which it doesn't. I haven't seen one that actually does. The scale is large and easy to read. IMO they're all mass produced in China, regardless of what you pay for them, being it $20 online or $65 from a brew shop. Markup makes up all the difference.
 
i use the tube the hydrometer came it as my sample tube and I don't lose any beer and never return it to the fermenter.

First off, there is little beer needed for measurement in the tube the hydrometer comes in and when I have finished the reading I drink the beer. That tells me if I have a bad batch that would need to be dumped. Since I am drinking the sample, there is no beer wasted.
 
For small batches, like yours, a refractometer only makes sense. The results, using the gravity correction calculator, can be as good as a hydrometer.

FWIW, measuring FG is only important as an indication of gravity stability, the yeast having done their job. If it comes in higher or lower than expected, there is usually not all that much you can do about it.

I bought my refractometer off eBay from one of the larger sellers from the North West. It's the "heavy duty" version "weighing 25% more" than the "economy" model, and surely doesn't feel flimsy. It was around $23 shipped, 4 years ago. It's supposed to have a corrected OG scale, which it doesn't. I haven't seen one that actually does. The scale is large and easy to read. IMO they're all mass produced in China, regardless of what you pay for them, being it $20 online or $65 from a brew shop. Markup makes up all the difference.

I've only had one beer stall during fermentation but it sat 2 weeks in the fermenter and was at a stable gravity for more than a week. I was about to bottle it when I thought better since the gravity reading was so high. Just the disturbance of moving the fermenter to the top of the table seemed to wake the yeast as it went on to complete the ferment and was a the expected final gravity a week later. Knowing that the gravity was much higher than expected kept me from bottle bombs. With a refractometer I might not have realized that the reading was dangerously high.
 
I've only had one beer stall during fermentation but it sat 2 weeks in the fermenter and was at a stable gravity for more than a week. I was about to bottle it when I thought better since the gravity reading was so high. Just the disturbance of moving the fermenter to the top of the table seemed to wake the yeast as it went on to complete the ferment and was a the expected final gravity a week later. Knowing that the gravity was much higher than expected kept me from bottle bombs. With a refractometer I might not have realized that the reading was dangerously high.

I don't understand that last part--a refractometer should give you a good reading. Is yours unreliable or is there something else I'm missing here?
 
Thanks again fellas. I think I'm gonna go with the refractometer. Saw some on Amazon for as low as 20 bucks. I'm thinking that those ones are of low quality though. Usually you have to pay a little more for the good stuff.
 
With a refractometer I might not have realized that the reading was dangerously high.

You are assuming that a refractometer cannot be used to calculate FG. That is false. The limitations of the refractometer is what you limit yourself to doing.

And OP welcome to the dark side! You won't regret it. You can also take cool pictures like this for your records.

View attachment 1493997257159.jpg
 
I don't understand that last part--a refractometer should give you a good reading. Is yours unreliable or is there something else I'm missing here?

With a refractometer you have to calculate what the FG really is from a higher reading. In my rush to get to bottling that day I may not have noticed the difference. With the hydrometer it was unmistakable. Direct reading always trumps calculated reading.
 
With a refractometer you have to calculate what the FG really is from a higher reading. In my rush to get to bottling that day I may not have noticed the difference. With the hydrometer it was unmistakable. Direct reading always trumps calculated reading.

The importance lies in the same readings 3-7 days apart AND them being at or near expected FG.

For example, if the refractometer shows an (uncorrected) reading of 1.035 after 10-14 days of fermentation, and again 3-7 days later, and they concur with the expected FG, it's ready to bottle. The OP can take a 2-drop sample every day using a thin glass rod, it won't impact his bottling volume. But he also doesn't get to taste it.

At some point in time the OP may want to fill his "hydrometer jar" with the last bit of beer left in the bottling bucket, shy of a bottle's worth, take a reading for the record (it should be close to the corrected refractometer reading) then happily drink it as a reward for his efforts.

Now after all that work ending up with only 8-10 bottles of beer is way more puzzling...
 
With a refractometer you have to calculate what the FG really is from a higher reading. In my rush to get to bottling that day I may not have noticed the difference. With the hydrometer it was unmistakable. Direct reading always trumps calculated reading.

I'm still missing something. I have to calculate what the FG really is from a higher reading? Are you saying that the refractometer isn't accurate when it reports a gravity number?
 
Why not use the hydrometer, and then use the beer that you took for the reading as the liquid that you will dissolve your priming sugar into? So take your sample, place that sample into a pot, and boil it and add the priming sugar. Then pour that back into the beer and then bottle.
 
Or just give your beer enough time, and it will be done. I never take FG readings until I'm bottling.
 
^ you have never broken a hydrometer or a floating thermometer inside the kettle or anything have you?

I would higher recommend against this unless you have never broken a single glass in your life.

Just realize that you will loose the beer and add more volume this way. You really should have a feel for the end of fermentation and only do two measurements

My hydrometer is 17 years old...I don't drink and brew so my equipment tends to not break ;).
 
How are you going to read it? Usually krausen cakes the sides of the fermenter. And you need to read it at eye level.

Dumping back a hydrometer sample seems unnecessary for maybe 4 ounces.

I'm not a beer hypochondriac, been doing it far too long and realized most things people get stressed out about in brewing are massively over blown bits of forum group think. If I had to read a hydrometer at a slight angle and was off a point from reality I wouldn't loose any sleep knowing my calculated ABV is off a few hundredths. If it reads consistently even at an angle one knows fermentation is finished.
 
I'm not a beer hypochondriac, been doing it far too long and realized most things people get stressed out about in brewing are massively over blown bits of forum group think. If I had to read a hydrometer at a slight angle and was off a point from reality I wouldn't loose any sleep knowing my calculated ABV is off a few hundredths. If it reads consistently even at an angle one knows fermentation is finished.

I was more thinking about those times where the krausen has covered most of the fermenter. It would be impossible to see.
 
You would need to do the calculations only to correct for the alcohol present from fermentation. There is no need to do the calculations in order to determine if fermentation is complete. Two identical readings days apart will tell you it is done. If you want to determine what that reading actually is for comparison to expected FG or to calculate ABV then the adjustment will be needed
 
I'm not a beer hypochondriac, been doing it far too long and realized most things people get stressed out about in brewing are massively over blown bits of forum group think. If I had to read a hydrometer at a slight angle and was off a point from reality I wouldn't loose any sleep knowing my calculated ABV is off a few hundredths. If it reads consistently even at an angle one knows fermentation is finished.

I'm going for my doctorate in analytical chemistry and I have broken a fair bit of glassware even being careful. It's taught me respect so far, but a few drinks + hydrometer = **** show. Lol you are a better man than I for not drinking on brew day. And I like nifty gadgets so no brainer for me
 
So is there any real difference between the $66 refractometer from Northern Brewer, & the 20 something dollar one on Amazon?
 
As long as they have ATC which is auto temp calibration they are all the same. Some may be dual scale showing brix or SG or even Plato but not a real heck of a lot of difference. I'd only get one from NB if it came free which they sometimes do. Go for Amazon, they are all relatively the same when speaking of handheld refractometers to my understanding
 
Often after kegging I'll pour off the trub into a tall jug and let the trub settle out. There should be enough beer on top for a sample. Or I'll forget and pour a sample from the tap later.

After you've done a few dozen batches that all attenuate in the normal range then taking multiple gravity readings of a perfectly well behaved ordinary beer is just adding unnecessary infection and oxidation risk.
 
I'm going for my doctorate in analytical chemistry and I have broken a fair bit of glassware even being careful. It's taught me respect so far, but a few drinks + hydrometer = **** show. Lol you are a better man than I for not drinking on brew day. And I like nifty gadgets so no brainer for me

I could see with that education you'd be a bit more particular about accuracy in your readings too. You probably have a high precision FG hydrometer with the thin whisp of glass...I've broken one of those. Broke a graduated cylinder by dropping my hydrometer into it so now I stick to the plastic ones, a few Erlenmeyer flasks, but not my first hydrometer that bugger is a tank. Knocking on wood now.
 
why waste your time with 1 gallon batches?

I guess the snarky answer is why waste your time drinking 40+ of the same beer? I love my 1 gallon batches. Faster brew days, more varieties. I've found overall my quality is better in my smaller batches, but that's probably just me. Everybody finds a brewing method that works for them.
 
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