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Chance of blowoff tube clogging?

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El Nino

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Well i have my first brew that actually needed the blowoff tube, and i was wondering if there were any signs i needed to change out the tube.

Right now it's kind of alternating small / big bubbles. It usually has bigger bubbles then goes through periods with smaller bubbles that increasingly speed up, then plop! Big bubbles again lol. Just wondering if this is normal when you're getting blowoff.

Using 5/16 tubing (seems to be the size that fits in the bung). Relax and have a home brew? Lol
 
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Sounds like everything is working as it should and your ferment is just fine. No need to change the tube. That same crud residue in the tube is also majorly in the fermenter. Not to worry. Your beer will taste great.
 
5/16" OD = 3/16" ID? That would be too narrow! 5/16" ID would be fine, probably.

1/2" tubing fits over the center stem of your 3-piece airlock. If there is a star-shaped restrictor on the bottom of that airlock, cut it off.
 
5/16" OD = 3/16" ID? That would be too narrow! 5/16" ID would be fine, probably.

1/2" tubing fits over the center stem of your 3-piece airlock. If there is a star-shaped restrictor on the bottom of that airlock, cut it off.

I just put a 5/16 tube right in the bung hole (lol) and skip the airlock. In any case there was no clogging, i was just curious since it was my first brew that needed the blowoff tube, and the krausen looked pretty thick
 
Be warned that 3/16" ID or 5/16" ID tubing is too thin when you really need it. Like when krausen is blowing off like there's no tomorrow.

Even that airlock stem can become a restriction. Krausen is very sticky, like porridge, and tends to clog narrow passages. There's a lot of gas that needs to go through that tube, and if there's any restriction whatsoever... pressure builds up... Boom!
Something's gonna give, and within a second you've got krausen and beer everywhere, including the ceiling!

But don't take my word for it, there are plenty of pictures (and posts) to back this up.

Most of use 1/2" ID tubing for that reason. Sometimes the tubing goes directly into the airlock hole without grommet.

I had the lid bulge using 1/2" tubing onto the airlock stem going into a 2 quart jug half full of Starsan. Ferm temps were 66-67F. It was breathing like an animal for several hours.
 
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Well it's still bucking away, doesn't seem any worse for it.

Hope there wasn't too much mess. Pictures?
That's where non-tight fitting lids show their advantage.

Does the blowoff tube go deeply inside the liquid in the blowoff jug? That could create extra pressure. It only needs to be under the surface, deeper is not better.
I tape the tubing to the jug so it doesn't yank out unexpectedly or when moving things around.
 
I just started a hefeweisen and am using 1/2" tubing but after reading these i took an undrilled stopper and made a hole to fit tubing through. That way it seals, holds it in and don't have the restriction from airlock tube. If this is not big enough then I have a 1" blow off tube but that does not fit tight in my bmb cover.
 
I have a 1" blow off tube but that does not fit tight in my bmb cover.

You could wrap some sanitized plastic wrap around it to make a snugger fit. Or enlarge the outer diameter in that area by sliding a 2-3" piece of larger tubing over it or slice a 2-3" piece of your existing tubing and wrap around the outside.
 
It fits through the hole but is just not quite tight enough for full seal water around it will slowly leak past. I like the idea of some plastic wrap, would take maybe one or two layers to make gas tight fit. 5 gallons in a 6.5 gallon bmb so there is some headroom to start.
 
If you use carboys for fermenting I recommend making a couple of these. After cleaning beer and krausen off my ceiling and walls I decided not to take chances again.

IMG_2480.jpg
 
I really like that setup for an small space, looks like it makes it more stable and secure versus just a big blow off tube.
Btw, on a side note I was given a glass carboy, dont know if I will use it but do the red handle things work well?
 
Btw, on a side note I was given a glass carboy, dont know if I will use it but do the red handle things work well?

A lot of people advise you to not lift a full carboy with them and I’m not saying they are wrong, but I haven’t had any issues using them to move around my full carboys. Eventually I’ll probably switch to the webbing style carriers but I have 10 Glass carboys so that’s a lot of money that I could use for things that are more important things to me.
 
Do not lift a filled carboy with one of those handles. It puts a lot of stress on the neck and could easily break.

But then again, if you follow my posts you will know that I advise against glass carboys in the first place. IMO it is not if one will break but when one will break. Then how bad an injury when it does.
 
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