Blow off tube

[comicsandbeer83]

I'm about to do a 5 gallon batch and my carboy I plan to use is also 5 gallons. The style is a northern English brown ale and the abv should turn out to be around 5.2%. My question is do you think I can get away with using a normal air lock or should I do a blow off hose? I wasn't sure since it's not a high gravity beer so maybe the attenuation of the yeast won't go so crazy perhaps? What are everyone's experiences with this? I have used 6.5 gallon car boys and the krausen never even comes close to the top on that. Even at peak fermentation.

 

[thumpersk_a]

Either way be prepared to lose some beer. I'd run a blow off if your running 5 gal in a 5 gal carboy. It's better to use your 6.5 if it's sitting empty or even a bucket over a 5 gallon carboy for primary. leave some head space. I usually try to account for Murphys law.

 

[KangerBrew6]

It doen't take much time or effort to set a blow-off tube. Better that than cleaning up stuff and thinking I wish I had etc...

 

[fartinmartin]

I have never used a blow off tube, IF you adhere to 25% free space in the FV you should need one either.

 

[Vandulus]

If you're fermenting a 5 gallon batch in a 5 gallon carboy, a blow off tube will work but as thumpersk_a said you're going to lose some beer. Here's what I've done when using a blow off in the same situation you're in:
- Shoot for 4.5 gallons instead of 5 as you'll want at least .5 gallons headspace
- If you can control the temperature, try to ferment it a degree or two lower than you normally would. This should help lessen how much you lose.
- Make sure the tube fits very snugly in the carboy's mouth otherwise the krausen may push it out.
- Be prepared to change the water used in the container where the blow off tube bubbles up through for the first few days of primary. Most likely it will get quite a bit of krausen in it. Using a spill pan underneath you're using a small container for the water.
- Check the blow off tube daily to make sure it doesn't get clogged.

 

[whovous]

Can I jump in and ask why changing the water in the bubble container is important?

 

[PackerfaninSanDiego]

never heard of changing the water in the "bubble container"(airlock), but what do I know.

 

[whovous]

Not the airlock, the container at the other end of the blow off tube.

 

[Takuie]

Just in case it decides to suck some back in after peak fermenting and/or a significant temperature drop. Never seen it happen myself, but have heard of it happening to others. It's just one of those things I write off as makes sense if you don't think about it.

 

[Vamptrump]

I think people have got it spot on already. If you absolutely are going to put 5 gallons in a 5 gallon carboy, use a blow off. Like others, I would advice either dropping down to 4-4.5 gallons are hunting down a clean 6.5 gallon.

I personally just put 6 gallons in a 6.5, and I'm thrilled I put a blow off on (normally just use an air lock). Not even 24 hours in, and it had blown clean through. Granted mine was a little bigger at ~1.064. But it's always better to be safe than sorry.

 

[user 30639]

I use a blow off tube every single time, just to be safe.

 

[adamranders]

I also use a blow off every time weather high gravity or not. Use it for the first few days till krausen subsides then switch to airlock. Also a 5 gallon carboy (at least mine) actually holds around 5.5 to 6 gallons so there is some headspace, but it's just too easy to use a blow off and not have to worry about an epic krausen event making a mess.

 

[Sailingeric]

Get a bigger bucket. I have been using the 8 gal/30 Liter Brewcraft bucket for my 5 gallon batches. Plenty of room. :rockin:

 

[Vamptrump]

Get a bigger bucket. I have been using the 8 gal/30 Liter Brewcraft bucket for my 5 gallon batches. Plenty of room. :rockin:

Isn't there a risk of too much head space, especially for a longer duration in that bucket?

 

[Sailingeric]

Yeast makes CO2, CO2 pushes out the air and since the CO2 is heavier it will sink down protecting the beer as long as you don't keep opening up the lid.

 

[Vandulus]

Can I jump in and ask why changing the water in the bubble container is important?

Maybe it's just me being anal about sanitization, but I feel more confident when the water filling the other end of the blow-off is clean and sanitized. Plus if you have a particularly active strain of yeast, that water can get nasty fairly quick. It's probably overkill, but when I'm spending $30+ and 4 hours a batch I don't want to take any stupid chances.

 

[adamranders]

Maybe it's just me being anal about sanitization, but I feel more confident when the water filling the other end of the blow-off is clean and sanitized. Plus if you have a particularly active strain of yeast, that water can get nasty fairly quick. It's probably overkill, but when I'm spending $30+ and 4 hours a batch I don't want to take any stupid chances.

I wouldn't leave the blow off on for more than a few days to a week, just until the krausen subsides, and if you put starsan in the blow off container you really shouldn't have anything to worry about as far as things growing in it, at least not for the short time stated above.

 

[PackerfaninSanDiego]

Not the airlock, the container at the other end of the blow off tube.

that's an air lock

 

[whovous]

If you look at it that way, everything is an airlock if it stops the flow of air into the wort. A lid on a bucket is an airlock. But if I run a blowoff tube from the fermenter to a bowl full of liquid, I'd call the thing at the end of the tube a bowl, not an airlock. Most of us visualize something quite specific when we say airlock, even if our vision is technically incorrect.

 

[chexjc]

If you look at it that way, everything is an airlock if it stops the flow of air into the wort. A lid on a bucket is an airlock. But if I run a blowoff tube from the fermenter to a bowl full of liquid, I'd call the thing at the end of the tube a bowl, not an airlock. Most of us visualize something quite specific when we say airlock, even if our vision is technically incorrect.

If I'm not mistaken, you couldn't call the lid an airlock. Maybe it locks the air out, but an airlock as we're concerned with in homebrewing has to keep air out, but also let the gasses escape. A blow off tube is effectively an airlock on a larger scale. I don't see what the harm is in using one for the entire duration of fermentation -- that's what I do. I'd say there's more harm in changing it out what with the small risk of contamination in that instant.

 

[adamranders]

Only reason I change out my blow off for an airlock when krausen subsides is I find it a pain to clean a blow off that has sat for several weeks. I know it can be soaked in pbw for a while but I try not to soak plastics for more than 5-10 minutes. I feel that the couple seconds to change it out has minimal chance of contamination.

 

[GHBWNY]

I use a blow-off for first few days of active ferm; switch to airlock to finish.

 

[whovous]

In other words, you use an airlock for the first few days, then switch to an airlock to finish. Or at least that is what you do if everything is an airlock, as we seem to have decided here.

 

[adamranders]

An airlock is what it is, a blow off functions as an airlock but is still a blow off. Done.

 

[chexjc]

In other words, you use an airlock for the first few days, then switch to an airlock to finish. Or at least that is what you do if everything is an airlock, as we seem to have decided here.

Haha! Actually, I realized a downside to the blowoff tube yesterday as I saw no activity 48 hours after pitching...That is, activity is often less obvious. I know something is going on inside the bucket because I can smell it working, but the length of tube + the amount of backpressure created by the sanitizing solution at the end of the tube = less frequent bubbles. I brew and ferment my beer twenty mintues away, so I have no choice but to use the blowoff tube to be safe.

 

[Ianflean]

Checked on my beer today and 48 hours in it has blown the red top off the airlock and created quite a mess. Shiiiiit. It's bubbling krausen through the airlock. I don't have any suitable tubing for a blow off., will it be ok to just change the bung and airlock in a few days when it's calmed down?

 

[adamranders]

Checked on my beer today and 48 hours in it has blown the red top off the airlock and created quite a mess. Shiiiiit. It's bubbling krausen through the airlock. I don't have any suitable tubing for a blow off., will it be ok to just change the bung and airlock in a few days when it's calmed down?

Should be okay to change it quickly, in the mean time spray the whole airlock mess down thoroughly with starsan, and try to keep it topped off with fresh starsan.

 

[Ianflean]

Thanks!