From normal airlock activity to none at all, in one batch

I’ve been using the SS Brewtech 7 gallon stainless fermenter for the past year, roughly 10-15 batches. The bubbling activity has always seemed normal: a couple days of vigorous bubbling, tapering off to no visible activity within a week or two. However, I brewed this past Saturday, and I haven’t seen a single bubble, though the gravity is dropping nicely (OG was 1.068, which was expected, and last night’s reading was 1.019). I’m looking at the blowoff tube several times a day, so there’s very little chance that the bubbling is just happening when I’m not there.

I’ve read earlier posts that say that an absence of bubbling doesn’t necessarily indicate a problem, but I can’t see how it would change so drastically from my last batch, brewed over Thanksgiving weekend, which had very typical bubbling activity, to this. The blowoff tube and the lid both seem very securely in place. Has anybody using a stainless bucket type of fermenter experienced this?

Thanks for any input -


I’ve never brewed in stainless, but I’d still be wondering about a pressure leak somewhere. That’s quite a drop in gravity without seeing bubbles. Is there a gasket on that fermenter. Any chance there’s a crack in it?

I’m positive there’s no crack in the walls or lid, and the only other places for a possible leak are the silicone seal between the lid and the bucket (seems unlikely the culprit, because the silicone is really pliant and the four clamps seem very secure), the o-rings on the ball valve at the bottom (very unlikely, since it’d be leaking liquid instead of gas), and the blowoff tube, I guess the most likely place for a leak at this point. I don’t even find it hard to believe that there could be a leak; just seems weird that it went from functioning perfectly, to no bubbling whatsoever, in the course of one batch. I did find it strange, upon getting the new bucket and assembling it earlier this year, that it didn’t come with a hose barb to secure the tube to the lid. I just looked at their website and see that they sell one separately, but it seems like an extra, since it wasn’t included in the overall fermenter package. I’ve just been jamming the tube through the hole in the lid, with no problems until now (though I still don’t know if that is indeed where the leak is (or even if there is a leak)).

The seal could have dried and deformed allowing some leakage or the leak could be from the blow off tube hardening. Spray the area of the blow off tube with a solution of Starsan to see if you get bubbles.

Great point. I’m sorry that I forgot to mention that I did do exactly that – around the BOT hole and the lid seal – and saw no bubbling, though that wouldn’t positively mean it’s not leaking from either place. I think I’ll use a little keg lube on both areas next time. For now, I’ll just be hopeful that the outward pressure will keep bacteria out.

Some times are equipment fails us, but the yeast continues on its way to completion. We have fewer worries if we are sure we pitched the right amount of yeast, at the right temperature, and controlled the fermentation temperature for the optimum range of the yeast pitched.

HHMMM, with four clamps, are they adjustable? Ifn so, maybe too tight and caused a distorted lid now? Try give the lid a slight spin, so you clamp in-between yer previous clamp points and relax the clamp pressure, gentle may be the idea… Sneezles61

Your wort gravity can’t have gone from 1.068 to 1.019 without producing some CO2 and it’s not staying in that confined space so it had to leak out someplace. @sneezles61 may be on the right track and/or it’s leaking around the blow off hose you mentioned.

I fully agree that it’s leaking somewhere. My point was really just surprise that it would have developed such an apparently major leak from one batch to the next (as opposed to seeing less bubbling, little by little, with each successive batch). Anyway, I’ll use keg lube on the seal and the BOT next time, and make sure the lid seal is fully seated, and also try sneezles61’s idea of clamping down on new spots on the lid (though the clamps are not adjustable, and seem snug, but not overtight).

I just took another reading before this post (1.012), and it smells good, so I’m not going to worry about it. I’m actually surprised that it has dropped so much in a week, though I’ve never actually taken a second reading earlier than two weeks out.

Thanks for the input, everyone - I’ll set a reminder to post how it comes out in a month or so.

Cheers -


you may want to try check yer gravity even 3 or 4 days after initial pitch. It might suprize you! Sneezles61

I think I will from now on. The gravity on this one has gotten down as low as I want it to go much earlier than I expected. Will be nice to start conditioning it ahead of schedule.

After conditioning it for a few weeks, I’ve just taken my first sip. It’s good, in case anyone’s dying of curiosity.

See no worries! And we do care and appreciate updating posts. Although I will admit that I wasn’t ‘dying.’ :grin:

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That seems to happen almost all the time! Sneezles61