This is my first brew, so I kinda look at it as a rite of passage, but I had 5 gallons of brown ale fermenting in a 6.5g carboy. The airlock was super active for the first 16-18 hours. Soon after that I came into the closet I was fermenting in to an explosion. Needless to say the carpets ruined in there with a gallon or so of wort and hops spread on my carpet, clothes, and walls.

I moved the ale to another cool location and used a sanitized blow off setup (like I should've from the start if I wasn't such a noob) and it was still active, bubbles every couple of seconds for the rest of that day.

That was 3 days ago and it seems it has quieted down substantially. Yesterday I observed 2 or 3 bubbles. Wasn't watching it closely but just poking my head into the room. Haven't had much time to watch today.

My questions are:

  1. Is this guy ruined?
  2. If it is still okay do I really need to wait the 2 weeks for when the kit said it would be ready or should I read the lack of activity as my sign it is done doing what it will do?
  3. Is there anything I could do in the current state to make things better for this batch?

I think regardless of what happens I'm going to try this again, if nothing else to prove I can do it.

Thanks for the help, in advanced!

1 Answer 1


Apart from your carpet, Everything Is Ok.

It's very normal during the active fermentation stage that a large amount of vigorous yeast comes to the top of the brew. If the amount of beer enables the foam to reach the top of the vessel (a carboy in this case), it will be pushed out through the air-lock. The airlock may also become clogged with yeast, bits of hops, etc. and cause a build-up of carbon-dioxide gas pressure which will shoot out the airlock, bung etc.

Different yeast strains behave differently in this manner. For example, wheat beer yeast strains for Hefeweizen style beers are notorious for this. Generally with these you don't bother with a "normal" air-lock, and only use a blow-off tube as you describe. The temperature of the beer also directly effects how fast the fermentation proceeds, generally warmer is faster (but not necessarily better!).

In terms of knowing when your beer is ready - generally the procedure is to measure the Specific Gravity (concentration of sugar) before fermentation, and then again when you believe fermentation is complete with a hydrometer. The generally accepted guide is that the fermentation is complete when the result is around the expected final gravity, and there has been no change in the final gravity measurement for 3 days. There are some caveats though. If the ambient temperature gets too cold for the yeast, fermentation will get very slow (but not stop), and the beer may appear finished, but then when the yeast warms-up again fermentation proceeds. On high gravity beers, the yeast may stop before the expected final gravity too (for various reasons).

It's very important to get the final gravity stage/reading correct when bottling into glass vessels, because if fermentation is incomplete (but then re-starts), the gas pressure can cause the bottles to explode resulting in serious injuries. If you are "bottling" into kegs or PET plastic bottles the danger from explosions is not so severe.

If you have not made gravity readings, I would wait 2 weeks just to be sure. Even once the very active "primary" fermentation stage is complete, there are still changes happening in your beer. The yeast is going dormant in the vessel, dropping out of suspension, and re-processing some un-tasty fermentation by-products. Given the extra-vigorous initial fermentation, it would probably be ready earlier than 2 weeks, but I'm erring on the side of caution based on the available information.

  • Thanks for the write up! This is very helpful. Unfortunately I didn't have a hydrometer when I started the batch but it is on it's way. I thought it was really interesting to watch the temperature change. During the really active period it was sitting around 74 degrees, now that it has slowed it is around the temp of the room, 68. I'll post back with the result. Thanks again! Commented Sep 10, 2019 at 1:21
  • Ah that's good, I was a bit concerned that it was fermenting "hot", and while 74°F / 24.5°C is on the warmer side, it's not too hot for an Ale. It's normal for a ferment to produce a small temperature increase.
    – Kingsley
    Commented Sep 10, 2019 at 1:30
  • Do you know what strain of yeast you used? Some yeast strains are extremely active and others not so much. In any case, most ale yeasts will perform better closer to 65 F than 68-74 F. More calm, and beer might turn out a little better. Cheers! Welcome to the hobby!
    – dmtaylor
    Commented Sep 10, 2019 at 13:15
  • 1
    This is a great answer, regarding your future brews, the reason why a brew bucket is used is not so much because of volume (although that is certainly part of the equation), but because where a brewbucket generally allows the krausen (foam) to grow vertically, the shoulders of the carboy compress and funnel the krausen thereby causing a LOT more blow off or messy foam. An inch of volume in the bucket it the same as something like 10 ft of carboy mouth width of foam. I made that number up and didn't actually do the math, but that gives you an idea of why it made such a huge mess.
    – Escoce
    Commented Sep 10, 2019 at 18:14
  • 1
    I meant to follow up: the beer came out okay. A little astringent until about 5 months after it was bottled. After 5 months it came out tasting really good. Thanks again for the help! Commented Apr 7, 2020 at 16:40

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