Forgot water with blow-off tube

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Jun 3, 2007
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I brewed a batch of IPA this morning (about 11:00 AM) that I thought went perfectly. When I went to check on it tonight (8:00 PM), I found that I stupidly forgot to put water in the container at the end of my blow-off tube. (I immediately corrected this). Currently, fermentation is very active (in fact, the most active of all the 8 batches I've brewed so far).

My question: Have I ruined this batch by forgetting the water? Is it now contaminated?

Thanks in advance!
Benny Blanco said:
You're fine. That's probably waaay on the bottom of things to worry about. :mug:

Thanks for your reply!

The frustrating thing was that except for forgetting the water, this was a perfect brew as far as I could tell.: no burnt LME, nice yeast action, proper pitching temperature, etc. I have high hopes for this one!
The contaminant would have to find it's way all the way to the inside of your fermentation vessel. It'd have to find hte tube opening and make it's way all the way through. You've already got an active fermentation, so you've been blowing carbon dioxide out already. No problems to worry about because of the lack of water, but good that you realized sooner rather than later.
Well, I'm sure it'll be a great brew.

I once took the top off my carboy to take a reading and forgot about it. Came back later that day and it was sitting there with no cap. If it was my first brew I would have freaked out, but I know the co2 would prevent anything from floating in there.

Don't sweat the small stuff.:D
If you refer to Pasteur's famous swan-neck flask experiment (google it) you'll see that you really have NOTHING to worry about. Contaminants in air are carried by dust particles, and dust cannot go UP a tube unless there is an air current to carry it - and not only did you have no air current going INTO the tube, you had a decent amount of CO2 being pushed OUT through the tube. I'd even go so far as to say that under most circumstances, there's not much real benefit of putting liquid in blowoff containers/airlocks at all - among the few cases I can see it being important is if you get suckback due to temperature swings, and to keep out fruit flies (which CAN go up a tube) out. But I digress - in short - you're all set!
I would assume oxygen could get into the beer if you do not have water in the tube. Hopefully enough activity didn't allow this to happen. You should be fine.