Minimum Headspace on Fermenting Bucket

[Ltkenbo]

I picked up some food grade 2 gallon buckets with gasketed lids and am planning on using them as fermenters for smaller batches.

I was wondering what the minimum headspace is that I could probably get away with and not have overflow out of my airlock. If I can get away with 2 inches that would be ideal because that will give me 1.75 gallons which should give me a approximately 1.5 gallons of beer. Was wondering if that's too small - if so I was planning on doing 1.5 gallons then (3 inches of headspace). I know this will depend on the yeast, but was wondering people's opinions based on their experiences.

 

[day_trippr]

Temperature controlled fermentations, or no?
The 1.75g option is bound to convey more drama than home brewing should entail.
I'd go with the 1.5g option, and a blow-off hose...

Cheers!

 

[Ltkenbo]

Temperature controlled fermentations, or no?
The 1.75g option is bound to convey more drama than home brewing should entail.
I'd go with the 1.5g option, and a blow-off hose...

Cheers!

Yes, temperature controlled fermentation.

 

[day_trippr]

Excellent.
The safest course would be to do a 1.5g batch and see how it goes, keeping in mind OG and yeast strain combinations can produce significantly different fermentations (eg: a 40 point wheat beer with 1010 is unlikely to run amuck whereas a 100 point imperial stout running on S04 can be volcanic )
If it looks like you could step up another quart on a comparable recipe, go for it on the next batch...

Cheers!

 

[Sparger]

I have no issues with cold temp lager ferments - little head space needed. I would use a blow off tube for an ale yeast, 68F, 1.06 or greater OG. In fact I got tired of the blow off tube hassle and bought a speidel fermenter for IPAs. They come with a massive airlock.