2.5gal brew in 3gal carboy

Is there enough headspace in a 3gal carboy for a 2.5 gal beer?

My thinking is:
5.5/6.5=.8462

1-.8462=.1538

So, for a 5.5 gal brew in a 6.5 gal carboy there is 15.38% headspace.

And

2.5/3=.8334

1-.8334=.1666

So for a 2.5 gallon brew in a 3gal carboy there is 16.66% headspace.

Sure looks fine in print but what about the real world? Is it enough headspace or should I just use 5 gal carboys?

Thanks guys

My Copper Dragon Ale just finished fermenting in a 3 gallon carboy (2.5 gallon batch). I did have to use a blowoff tube, but I didn't lose much. I think I just had a very active fermentation other wise it would have been fine.

Right on!

Thanks

yep. blow-off tube

For anything except a wheat, yes.

would a 5.5 wheat brew not work in a 6.5 carboy?


hmm bc I really like hefes....

it'll work, but you may get a ton through your blowoff tube.

i'm blowing alot through mine right now...5.25 gallon in 6.5.