Just wondering if I should agitate the carboy during fermentation/towards the end when it starts to slow?

1 Answer 1


You can if you want. I find it to be helpful sometimes in knocking the krausen back down so the yeast will settle out sooner.

Also, I sometimes swirl the fermenter gently to blend some yeast back into suspension on purpose to ensure full attenuation for yeasts that flocculate too quickly.

Use your best judgment. If you think you should, I say go ahead and do it. Just be gentle so that you aren't adding a lot of oxygen back in, as that could lead to faster staling.

  • Where is the oxygen coming from?
    – brewchez
    Commented Mar 2, 2020 at 15:36
  • Good point. Potential for air suckback through the airlock based on pressure differentials... assuming an airlock is installed. If no airlock, well then there is your air source obviously.
    – dmtaylor
    Commented Mar 2, 2020 at 22:17
  • OK just asking for clarity of others. Usually when I shake a carboy/fermentor that has undergone some fermentation the airlock bubbles OUT due to knocking CO2 out of solution. But I could see if fermentation was weak and the air in the headspace hadn't been displaced then maybe this would be an issue. I think we agree in general agitation of a fermentor isn't necessary if all things are going well.
    – brewchez
    Commented Mar 3, 2020 at 12:51

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.