Rookie question - sanitized hydrometer reading

[Muskietooth]

Rookie question here. How do I best take a hydrometer reading?

I’ve brewed a few kit batches and currently have 5 gallons in a bucket style fermentor. In the past I’ve only taken a hydrometer reading after boiling and then again at bottling. Reading more on here I feel like I should take readings during fermentation as well to get more data and see when it’s complete. However how do I do that safely?

Pour out the spigot then waste the 8 or so oz? Will this pull air in through my airlock?

Open the top and take a reading? Won’t this get rid of all my c02 that’s protecting the beer? I worry that if I take a reading and it’s complete if I can’t bottle for a few days I’ll end up with oxygen above the beer in the bucket.
Thanks!

 

[RM-MN]

What I usually do is leave the beer for 2 to 4 weeks in the fermenter, take a reading then and if it is close (really close) to the expected FG I bottle it. I have had only one stuck ferment and it restarted right after I took the sample and was ready to bottle a week later.

If you really, really want to have a record of how the fermentation progressed a Tilt hydrometer that you leave in the fermenter (closed lid) and get readings on your smartphone or computer.

 

[Golddiggie]

Another option is to use something like a Tilt to get the readings without pulling any samples.

 

[Muskietooth]

@RM-MN when you do measure do you put your hydrometer in your fermentor? Or pull a sample from a spigot?

 

[wsmith1625]

The easiest method is to open the bucket and safely drop your sanitized hydrometer into your beer. Get a quick reading and seal it back up. Used that method with no problem for many brews. I've also used the spigot, but would crack the lid open so the starsan in the airlock didn't get sucked into the beer. Both method will introduce some oxygen, but it's very minimal and should have little to no detectable effect on most beer styles.

 

[Golddiggie]

Most ales (below ~7-8% ABV) can be done fermenting in a week (or less). Bigger beers can take longer to ferment fully. I typically give a brew (sub 7%) two weeks for the yeast to do it's job, and then go to sleep. Then I carbonate and package. With temperature control, this can be easier and give you better beer. Without temperature control, you could need to give a batch longer post fermentation for the cleanup stage.

I would advise being very frugal with taking readings where opening up the fermenter is involved. Learn patience and the yeast will reward you. IMO/IME, it should be one of the easiest things you can do for your beer. As you evolve your methods, and gear, you can streamline your process and [possibly] shorten grain to glass times. IME, carbonating (fully) in fermenter (conical) is one of those items. It's not for everyone due to the costs involved, but it sure does make things easier.

 

[DBhomebrew]

A refractometer requires just a few drops from the spout. A half ounce gives a good taste too.

 

[camonick]

Pour out the spigot then waste the 8 or so oz?

I use a 10” hydrometer test jar to take my readings and it only requires 4oz of liquid. I mark mine with a sharpie so I know where to fill it.

 

[wsmith1625]

As a rookie brewer, taking gravity readings is an important step in learning about fermentation processes. When you're more experienced, readings may be less necessary. One safety concern however is bottling too soon. This could create bottle bombs which could be dangerous and will ruin your batch of beer. Using gravity samples will confirm when fermentation is complete and eliminate that risk.

 

[Golddiggie]

For the rookies... If you give the batch enough TIME you won't have issues. I might have checked the first two batches during the process (over a decade ago now, so not even sure on that). But I quickly learned that if you give the batch some more days beyond when things appear to be settled, you get something even better. Plus reduce chances of bottle bombs.

Pretty quickly I just took samples on packaging day to see how close to the expected FG I hit. Pretty much the same I did before I got the Tilt units. I still spot check batches to compare readings with a digital refractometer. I do that for OG and FG. Not every batch, but when I feel like it.

 

[Muskietooth]

Let’s say I just wait the two weeks and don’t take measurements during fermentation as some of the advice in this thread suggests - do I then just wait until bubbles in the airlock are less than one every 2min? Or no bubbles whatsoever? How do I then know if fermentation is complete?

 

[wsmith1625]

How do I then know if fermentation is complete?

Bubbles in the airlock are not a great measurement of fermentation. Yes, when it's going crazy you definitely have active fermentation, but when it stops bubbling, fermentation may not be complete. A leaky bucket lid can contribute to that. Also, sometimes bubbling will continue after fermentation is complete due to temperature swings causing co2 to escape from the beer.

Krausen is a better visual sign of fermentation. If you open the bucket and see a ring on the sides, but nothing on the beer, it's likely done. If you have active krausen, it's not done and needs to finish.

Two weeks is a good rule of thumb, and a third week for cleanup is an option too. But if your not sure, take a gravity reading to confirm your instincts.

 

[Stormcrow]

I usually just wait two weeks now (more if I get busy) and take the sample on the day I'm ready to bottle. I haven't had one not ready by then...yet.

I can definitely relate to wanting to gather more data starting out though. For what it's worth, here's a little anecdote. I started out doing two or three gallons at a time split up in one gallon carboys. I would sanitize everything real good, auto siphon a sample into my test jar, take the reading, and dump the sample right back in. (Saving a sip for myself of course. ) With batches that size, I just couldn't bring myself to discard the samples and wanted to save every drop possible. I'm sure it added oxygen. And it probably should have gotten infected, but I don't recall every having noticeable negative consequences. I don't feel the need to do that anymore, but you might be surprised what you can get away with.

 

[davidabcd]

If there's no big temperature change, the bubbles will stop, based on dozens of batches.
I wouldn't be comfortable using that but I am comfortable waiting three weeks, never opening the fermenter.
I take two readings, the second one to confirm I've reached expected FG and then I immediately bottle.
I don't recommend any of what I do right out of the gate. If you start with kits and you get a kit OG and a the kit FG after three weeks, it's safe.

 

[RM-MN]

@RM-MN when you do measure do you put your hydrometer in your fermentor? Or pull a sample from a spigot?

Actually, I do neither. I'm skeptical about using a fermenter with a spigot after having broken on on the bottling bucket. I'm also skeptical about putting my hydrometer into the fermenter as I have trouble reading it there. Instead I sanitize a turkey baster and draw samples with that. For a test sample I use the tube my hydrometer came in, holding it in one hand while I collect the sample, then setting it into a glass tumbler to keep it from tipping over while I put the lid back on the fermenter and clean out the turkey baster. The hydrometer tube is smaller than the hydrometer test jar shown in post #8 and after I have recorded the reading I remove the hydrometer and drink the sample. While the sample does not taste like the carbonated beer will it does give indications of problems with the beer before bottling, like the sour flavor from using too much acid to adjust mash pH.

 

[Brewdog80]

The mark must be at level the hydro would float at 1.000. But I drain out of the spigot into the hydro with the hydro in it till it floats. Let it sit for a couple of minutes if bubbles and get reading. Then I DRINK at least some of the brew. It gives me a decent idea if I did good job or the brew will be a stinker

 

[thomer]

Another option is to use something like a Tilt to get the readings without pulling any samples.

I also use Tilts. While not cheap, they are really convenient to use and prevents oxygen from being introduced into the beer. Only issue I have occasionally is batteries dying half way through fermentation.

 

[Golddiggie]

I also use Tilts. While not cheap, they are really convenient to use and prevents oxygen from being introduced into the beer. Only issue I have occasionally is batteries dying half way through fermentation.

They really should have a battery bar on the software for these. That way you KNOW how much is left in them. At least with the pro models, they use AA (lithium) batteries. So no need to recharge them. Down side of that is how much larger (OD) they are. They won't fit through a 1-1/2" TC port in my conical lid. If I get the conical from Brewers Hardware, the larger opening (3" TC port in the lid as well as a couple of 1-1/2") would let me drop it in easier than with the Spike CF10 fermenters I use now.

 

[thomer]

I use the 'standard' tilt model so I don't have that issue. With buying my BIAB Electric Kit the pro models were just a bit too expensive for me. And yes you are absolutely correct, having a battery bar is a pretty simple addition.

 

[hotbeer]

Find something smaller in diameter than those big cylinder flasks they give you to use with your hydrometer and you won't be pulling as big a sample out of your fermenter. I have found the plastic tube my hydrometer came in works really well. I set it in the big oversized sample cylinder they sold me to hold it upright when I check SG.

 

[TestTickle]

A refractometer requires just a few drops from the spout. A half ounce gives a good taste too.

+1 to a refractometer.

 

[Golddiggie]

+1 to a refractometer.

I used the manual refractometers for years. Last year I picked up the digital one. Doubt I'll go back to the manual one unless forced to. With my eyes, it's far easier to use the digital one.
https://smile.amazon.com/gp/product/B007Z4IN58

 

[DBhomebrew]

I used the manual refractometers for years. Last year I picked up the digital one. Doubt I'll go back to the manual one unless forced to. With my eyes, it's far easier to use the digital one.
https://smile.amazon.com/gp/product/B007Z4IN58

I don't doubt it. But the 10x jump in $$ makes it less of good solution for the beginner brewer.

 

[Golddiggie]

I wouldn't trust a sub $20 refractometer. Hell, I wouldn't trust a sub $50 one. I had one of the cheap, or "budget" ones before and it sucked balls. Any "dual scale" model, IMO, is worthless. The cheapest one I bought was about $70 for 28-62 Brix reading. The ones that went from 0-20 and 0-32 were just over $100 each (back in 2015, a bit more now).
One of those is still available:
https://www.amazon.com/gp/product/B004WDRJUU
IME/IMO, buy quality one time, or buy cheap several times. End cost is pretty much the same (since you often have to replace the cheap ones several times where the better one just keeps working).

 

[TestTickle]

I used the manual refractometers for years. Last year I picked up the digital one. Doubt I'll go back to the manual one unless forced to. With my eyes, it's far easier to use the digital one.
https://smile.amazon.com/gp/product/B007Z4IN58

I have the same one, and while it is easier to read, I agree with @DBhomebrew.

 

[TestTickle]

I wouldn't trust a sub $20 refractometer. Hell, I wouldn't trust a sub $50 one. I had one of the cheap, or "budget" ones before and it sucked balls. Any "dual scale" model, IMO, is worthless. The cheapest one I bought was about $70 for 28-62 Brix reading. The ones that went from 0-20 and 0-32 were just over $100 each (back in 2015, a bit more now).
One of those is still available:
https://www.amazon.com/gp/product/B004WDRJUU
IME/IMO, buy quality one time, or buy cheap several times. End cost is pretty much the same (since you often have to replace the cheap ones several times where the better one just keeps working).

I agree with staying away from the dual scale models, mainly because it causes confusion with new brewers and final gravity readings. However, in addition to the Milwaukee digital refractometer I purchased a couple years back, I still have the first refractometer I ever purchased - a $20 model from Amazon. I have never had an issue with its accuracy. In fact, I get the same readings with both refractometers as well as with my hydrometers any time I have compared them. The only reason I bought the digital was for easier readings.

 

[JohnDBrewer]

For a new brewer I would suggest after you have pitched your yeast give the fermenter a good couple swirls to make sure the yeast is fairly well distributed pull a sample big enough for your hydrometer container, plus a little. This sample will never go back into the fermenter but kept in a separate container. A beer bottle with a piece of foil works nice. Keep this container with the main fermenter so it stays at the same basic temperature conditions. Now you can measure the specific gravity whenever you want without wasting any, worrying contamination or oxygen egress. This sample is basically going to track your main fermenter's progress. Not exact but close enough. Cheers

 

[odie]

I've tried a refractometer...never could reconcile the readings with my hydrometer

 

[Golddiggie]

I've tried a refractometer...never could reconcile the readings with my hydrometer

I initially compared the hydrometer to my refractometers (manual) and they were in sync. After that, I left the hydrometer alone, stored away, only to be found recently because I was looking for something else. I'm not talking the cheap refractometers that I'm sure many buy.

 

[JP_BeerFan]

Find something smaller in diameter than those big cylinder flasks they give you to use with your hydrometer and you won't be pulling as big a sample out of your fermenter. I have found the plastic tube my hydrometer came in works really well. I set it in the big oversized sample cylinder they sold me to hold it upright when I check SG.

For something self standing, for the hydrometer crowd.... I did a lot of Amazon research, and got one of these:
Amazon.com
100ml, and it floats my (Brewmaster, do they vary in volume?) hydrometer in about 105-110ml water, with about 1.5-2" more pourspace left before overflow. Not glass clear, it's polypropylene, so a bit translucent but still easy to read. Very tough, will never break, you could boil it with no problem.

I got the classic, 250ml el cheapo at the LHBS, with the screw on bottom, it was some nicely clear but brittle plastic (styrene?) and the bottom cracked and leaked about the 2-3d time I cleaned it.

 

[GrowleyMonster]

Another vote of confidence for the Tilt. Absolute accuracy might be a couple of points off but comparative accuracy will be spot on the money. So it will tell you if your gravity has stayed exactly the same for the past three or four days or whatever, and you know your ferment is done and you can transfer to keg or bottle if you wish, or leave it in the fermenter to clarify a bit more, whatever. You don't have to open the fermenter. You don't have to take a sample from the spigot and suck air in through the airlock. You drop it in when you pitch yeast and it just stays in there until you rack out.

However, if I had known about the iSpindel when I started, I would have got one of them or a kit of parts for one. It is cheaper than the tilt and uses wifi instead of bluetooth. Longer range, and should be able to set it up as a network resource pretty easy. But anyway I strongly suggest getting one or the other. As a bonus, you get temperature, too. With a big beer, the beer can be over 10 degrees warmer than the ambient temp. My room temp was fine for my last bottled batch but I got a lot of heavy citrus in the unconditioned beer, and I suspect it is because the temp was, at 76 degrees, near the top of my yeast's working range. So knowing your temp is probably even more important than knowing your gravity. You can tell when it is done. No airlock bubbles, no micro bubbles floating up in the beer, (well, you need a clear fermenter to see them.) and all the cloudiness will clear up. Generally. But you don't know the temp way inside the fermenter. Just feeling the outside won't tell you anything much. Float a Tilt in there and you can always know what the temp is, what the gravity is within a couple of points, and if either has risen or fallen at all in x amount of time.

A nice thing about the digital hydrometers is that they self correct the gravity for temperature. And you can calibrate them in a known gravity solution. You know distilled water has a gravity of 1.000. You know if you calculate a solution at 1.100 that the reading should be 1.100. So you can adjust the calibration, or you can make a correction table, whichever. The truth of the matter is, a couple of points in OG doesn't really matter, and a couple of points in FG barely matters at all. You are looking for a stable reading that is no longer falling.

But if you just got to do it old school or cheap charlie style, the tube that most hydrometers ship in can be used for a sample tube and it uses way less beer than a regular sampling tube. You just have to fiddle with it, rock it slightly to keep the hydrometer unstuck from the tube wall. My suggestion is go with one of the floating digital type. The Ispindel is only about $55 or so, assembled and ready to use.

 

[bracconiere]

the tube that most hydrometers ship in can be used for a sample tube

just remember to never use it for hot wort, to get your OG reading....put a serious bend in mine... (i'm lucky i can get it in and out at all now...)

 

[jambop]

This is probably going against opinion but I think far too much emphasis is put on air borne infection risks. I once had the great pleasure of visiting Belhaven Brewery near Dunbar Scotland back in the late seventies . This place was very old school and the fermentation vessels were more or less unguarded save for a ramshackle plank wood cover ... they never had an issue. Times have changed but they made very good beers there. I think infections are far more likely from dirty equipment during the fermentation period eg. vessels not properly sanitised before transfer and tubes and taps used not properly cleaned and sanitised .

 

[BrewnWKopperKat]

But if you just got to do it old school or cheap charlie style, the tube that most hydrometers ship in can be used for a sample tube and it uses way less beer than a regular sampling tube. You just have to fiddle with it, rock it slightly to keep the hydrometer unstuck from the tube wall.

A simple alternative: adjust the batch size to include enough wort for additional FG measurements.

And, FWIW, it's a classic technique .