Active Fermentation and Blow Off Tube

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:


New Member
Nov 25, 2012
Reaction score
Question for ya'll. I went to the AHA Rally at Heretic on Saturday and got a five gallons of wort. I used White Labs Best of Both Worlds WLP 200 and pitched it on Saturday, April 29 in my bottling bucket bucket. My wife sent me a picture today of the bottling bucket and wort was coming up through the air lock. I got him and made a blow off tube by inserting my siphon tube into the piston of the air lock and then putting the other end of the siphon tube into a pitcher filled with water and a little Io-Star. The initial water I had in the airlock was not sanitized water. It was from the tap. Also, I took the airlock off and cleaned it off by running it under water and I then put it back in the bung on the lid of the bottling bucket. I did not re-sanitize the airlock. Did I run the risk of contaminating my wort?

Also, since creating the blow off, I am not seeing any bubbling? Could it be that active fermentation has finished? Thank you!


Well-Known Member
Sep 4, 2012
Reaction score
Las Cruces
Yes, you run the risk of contaminating your wort. It is, however, a minimal risk, I think. It certainly sounds like fermentation was pretty far advanced by the time you switched out for the blowoff tube, and the alcohol should help resistance to infection. Watch it until you can verify, by SG readings, that fermentation is finished. Hope for the best.