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Improvised bucket blowoff

My second batch ever is furiously bubbling away in primary. Tuesday at 6PM I pitched the yeast into my standard NB ferm bucket I didn’t notice any activity before going to bed some 4 hours later but less than 24 hours later my wife called me describing a decent bit of blow off. Not well prepared for this event I used what I had on hand. I was able to get a nice tight seal with my siphon tubing on the lid grommet and so used that as blowoff sticking it in a bucket of sanitizer solution. Still plenty of co2 activity but no more overflows so I don’t know how effective this setup would actually be for a blowoff. Any thoughts?

If you have a 3 piece airlock you can fit a hose over the center stem of the body. Best option for a bucket.

What was the temperature? Most times you can avoild blow off by fermenting at lower temperatures. You’ll get better results in your finished beer as well.

Generally speaking you want o ferment at the lower end of the yeasts’ optimal temperature range. This is typically in the low to mid 60s.

If you search this forum or just google ‘swamp cooler’ you’ll see more discussion and some ideas about how to keep your buckets chilled.

That should be fine. You may want to think about keeping the temperature down since blowoff may be the result of a too rapid fermentation, unless you are brewing a high gravity beer with an active yeast. Search on swamp cooler.
Fermenting wort generates heat so it will run at a higher temperature than the room.

What Danny said, with the caveat that some yeasts are notoriously active and are always likely to go crazy. Always best to be prepared… sounds like your improvised solution should be okay. Now that the overflow has subsided, but you have decent co2 pressure, is a great time to either replace the airlock with a clean one, or clean the dirty one, replace the fluid in it, and reinstall.

I will say, I love the 3 piece airlock, and will never go back to the S shaped. Ease of blowoff assembly, ability to clean better, and ease of topping off sanitizer are my reasons.

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Thanks for the replies. I had already ordered 3 piece air locks and cleaned the s lock. Though I’m waiting to uninstall the blowoff tube.
The beer is La Petite Oránge Belgian dubbel so it’s a decently strong beer (6.1%abv extract kit) with the Belgian dry yeast. I intentionally let it ferment at room temp 70+ degrees here as many people reported little to none of the esters associated with Belgian ales when fermenting this recipe at lower temps. I suppose I should have anticipated a blowoff in retrospect.

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I appreciate the insight on those air locks. I’m glad I got some on the way. Along with (finally) a hydrometer.

Remember that during active fermentation, the wort temp can be several degrees higher than the room temperature because the fermentation is generating heat. The higher the wort temp, the more active the fermentation so the more heat generated, which means still higher temp. It can become somewhat of a runaway situation.

If the blowoff is really going, it can even clog a 3 piece airlock. I had it happen once and blow the bung out of a carboy. What a mess that was ! You can use a larger blow off hose to really be safe. See this post for pictures and more info.

That’s a reasonable temp for a belgian but as @uberculture alluded to above some yeasts, like belgian yeasts, will be highly active even at lower temps. Sounds like you have it under control.

The flow rate through the body of the three piece air lock can be increased by cutting off the taper at the end.


I do use the big mouth bubbler. In the hole of the bubbler i stick a bigger hose that fits tight in hole. And dont use the. Airlock. Before active fermenting stops.

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