Noobs, don't trust your airlock

This is a great piece from homebrewtalk.com that I stumbled across today while searching about:

"Your HYDROMETER is the only BEST indicator of fermentation activity. Nothing else is accurate or consistent…

Unless you take a gravity reading you don’t know what’s really going on, not by airlock bubbling or by krausen formation. Neither of those signs are effective, they don’t tell you exactly where on the fermentation process you are.

The amount of krausen can vary for whatever reason, it can come quick and depart quickly or it can linger long after fermentation is complete, and it all be normal.

And airlocks sometimes bubble or they don’t.

If your airlock was bubbling and stopped—It doesn’t mean fermentation has stopped.

If you airlock isn’t bubbling, it doesn’t mean your fermentation hasn’t started…

If your airlock starts bubbling, it really doesn’t matter.

If your airlock NEVER bubbles, it doesn’t mean anything is wrong or right.

Your airlock is not a fermentation gauge, it is a VALVE to release excess co2. And the peak of fermentation has already wound down, so there’s simply no need to vent off any excess co2.

Fermentation is not always “dynamic,” just because you don’t SEE anything happening, doesn’t mean that any-thing’s wrong, and also doesn’t mean that the yeast are still not working diligently away, doing what they’ve been doing for over 4,000 years.

That’s why you need to take a gravity reading to know how your fermentation is going, NOT go by airlocks, or size of krausen, or a calendar, the horoscope or the phases of the moon (those things in my mind are equally accurate).

The most important tool you can use is a hydrometer. It’s the only way you will truly know when your beer is ready…airlock bubbles and other things are faulty.

The only way to truly know what is going on in your fermenter is with your hydrometer. Like I said here in my blog, which I encourage you to read, Think evaluation before action you sure as HELL wouldn’t want a doctor to start cutting on you unless he used the proper diagnostic instuments like x-rays first, right? You wouldn’t want him to just take a look in your eyes briefly and say “I’m cutting into your chest first thing in the morning.” You would want them to use the right diagnostic tools before the slice and dice, right? You’d cry malpractice, I would hope, if they didn’t say they were sending you for an MRI and other things before going in…

Thinking about “doing anything” like repitching, or bottling, or racking, without first taking a hydrometer reading is tantamount to the doctor deciding to cut you open without running any diagnostic tests…Taking one look at you and saying, “Yeah I’m going in.” You would really want the doctor to use all means to properly diagnose what’s going on?

Sorry but that really is the only answer that is accurate or consistant, the numbers on the little stick. I have had evrey airlock bubbling/non bubbling/slow bubbling/fast bubbling/little krausen/big krausen/slow forming krausen/krausen staying 3 weeks after the hydro showed terminal gravity scenario imaginable in nearly 1,000 gallons of beer, and none of that stuff is as sccurate as 30 seconds with a hydrometer."

Useful info, for sure. If you went through and changed “hydrometer” to “refractometer” it would be even better. :wink:

Big Ballin’! $_$

For the record… theres plenty of surgeries that are appropriate to do without a CT scan or MRI!

Now carry on with your refractometer / hydrometer’ing.

I thought the refractometer doesn’t read accurately after fermentation has begun, what with all the alcohol diluting the sugar and water.

I thought the refractometer doesn’t read accurately after fermentation has begun, what with all the alcohol diluting the sugar and water.[/quote]

Using a “correction factor” you can get a good idea what the SG is post fermentation.

:wink: [/quote]

Big Ballin’! $_$[/quote]

Refractometers can be picked up for under $30 on ebay.

I have buckets and lids that sometimes leak. I can have a great fermentation going on and see no airlock activity. I don’t sweat it, I know I’m making beer.

[quote=“Nighthawk”]Using a “correction factor” you can get a good idea what the SG is post fermentation.[/quote]You can get within 0.002 or so of the actual gravity which is well within the reading error if you’re using a normal-scale hydrometer instead of the low-scale model (0.980 - 1.020). Plus the refractometer only takes a drop of wort which you can retrieve from the fermenter with a stainless skewer, making it much easier and faster to use than a hydrometer. Of course, you have to then sit down at a computer to convert the number.