How much headspace is too much?

If I'm fermenting 5-gallon batches, is 2 gallons too much head space? 3 gallons? 5 gallons?

How much is too much?

What are you brewing? ales? Typically you do not have to worry about head space, CO2 realeased from the beer provides a protective layer if you will, over your beer keeping from exposure to oxygen. If however, you were brewing wine, then you would be more cautious. I brew 2-3 gallon ale batches in my 5 gallon carboy all of the tie with no problems.

Head space is really a concern if you are long term aging, like with a really heavy beer or a wine. For average beers that will be out of the fermenter in a couple / few weeks not an issue IMHO. Just don't be opening the fermenter every day like a noob...let it be!

There is no set number on what is too much head space...the more secure your fermenter, the longer you can let it sit...I ferment in a stainless kettle w/ the lid on...but typically move to keg right pronto. Also the longer you want to cellar your beer, the more concern...for ales meant to be consumed rather fresh....RDWHAB

It's not much of a concern at all for most homebrewers. There are several open fermentation methods that completely ignore the concept of a bubble lock/blowoff tube and just let the beer krausen gurgle away as the beer ferments. If your brew setup is in a clean environment and you pitch adequate amounts of yeast into a cleaned and sterilized fermenter, you should be fine.

Much appreciated Guess it's time to stop worrying and just kick back

I have a similar question. Should I make it a new thread?

I'm looking at switching to a glass carboy for my primary fermenter instead of a plastic bucket. I see 5 gallon, 6 and 6.5 gallon sizes. My thought is I'd want the least headspace possible.

True? Thanks.

For a primary fermentation vessel you want bigger. I've always used a 6.5 gallon carboy for 5 gallon batches, and even then I've had a few tops blow off due to very active fermentations (which is why I'm switching to a blow off hose).

For secondary fermentations you might start to worry about headspace since the yeast will be less active and put out less CO2. Even then, with shorter fermentations (< 1 month) you don't really run the risk of oxidizing your beer with a larger carboy.

yes no need to worry.. even if your fermentation doesnt even create enough c02 to move the airlock, if its fermenting, it has created enough to generate a layer above the beer.. co2 is heaver than air, so no need to worry..

i have fermented 1-2 gallon batches in 6.5 gallon glass carboys without a prob

aquenne said:

yes no need to worry.. even if your fermentation doesnt even create enough c02 to move the airlock, if its fermenting, it has created enough to generate a layer above the beer.. co2 is heaver than air, so no need to worry..

i have fermented 1-2 gallon batches in 6.5 gallon glass carboys without a prob

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Did you get a lot of bubbling out the tube or airlock? Not Concerned yet but I did 3 gallons of cider in my 5 gallon bucket and waiting for bubbles.

KYchemBrewer said:

I have a similar question. Should I make it a new thread?

I'm looking at switching to a glass carboy for my primary fermenter instead of a plastic bucket. I see 5 gallon, 6 and 6.5 gallon sizes. My thought is I'd want the least headspace possible.

True? Thanks.

Click to expand...

I say False, for a primary, you want as much headspace as possible, just ask the many of us that have had a "wort explosion" out the top of a fermenter that was too small...hahah. Ok, you've been warned.

I do 2 gal batches in a 5 gal bucket... I have a 3 gal better bottle for long term projects after active ferm is done in the bucket.

wilserbrewer said:

I say False, for a primary, you want as much headspace as possible, just ask the many of us that have had a "wort explosion" out the top of a fermenter that was too small...hahah. Ok, you've been warned.

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+1

I also like to get 5 gallons of beer from a five gallon recipe instead of only 3 or 4 gallons with the rest flowing out a blow off tube.

bosco