I made a beer from extract (amber dryed malt extract). Recipe says OG is 1.040 FG is 1.010. Used Safebrew S-04 (english ale yeast). The wort has been sitting in primary fermenter for 10 days now. First days I had a lot of bubbles. Now a small bubble every 2-5 minutes or so. This seems to happen more when there are room temperature variations or vibrations. I do not have hidrometer to test FG.

Can I bottle? Generally speaking what airlock activity is acceptable for bottling?

  • 2
    you should get a hydrometer...
    – mdma
    Feb 20 '13 at 16:18
  • 5 answers and not a single up vote on the question? What's wrong with the question answerers?
    – brewchez
    Feb 21 '13 at 23:19

As others have stated, airlock activity doesn't mean much. For what its worth I bottled a cream ale while secondary was still bubbling albeit at a rather slow clip. It had sat a week longer than recommended so I figured I was safe, turns out I was right. Brew tastes fantastic.

buy a hydrometer and learn to use it, honestly its your best bet to ensure everything is finishing the way its supposed to. A bubble every few minutes wouldn't concern me too much.


I wouldn't rely completely on airlock activity. You should take a gravity reading with your hydrometer or refractometer at the same time each day for 2-3 days. If the gravity doesn't change, then fermentation should be complete and you can go ahead and bottle.

Airlock activity isn't a reliable way to determine if your beer is done fermenting or not. The yeast may simply be in an anaerobic state and not releasing much CO2 as a result.


An airlock does not provide a good indication of fermentation activity. You can have significant bubbling without fermentation or significant fermentation without bubbling.

The only thing reliable way to measure fermentation is to take two gravity readings separated by a few days. If your final gravity is steady and near where you expected it to be, you can bottle. Otherwise, you should wait.


Because of holidays and illness I had a beer last year that stays 4 weeks in the primary fermenter, also with S-04. Bottled after this period and it became a good beer. Generally you can better wait longer then shorter (bomb risk).


Hard to say, your yeast could be just slacking and get back to action when aroused by your bottling.

Usually 10 days are enough for fermentation of regular gravity beers like that one.

But if it isn't you risk having some 'bottle bombs' (yeast producing a lot more co2 than you expect and literally exploding the bottles).

You can risk that bottle and leave then in some place easy to clean (and be very careful handling those until you are sure they won't explode), or you can wait an week extra just to be safe and watch the airlock. Or better yet, if you can, get an hydrometer.

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