How much headspace in primary?

[william_shakes_beer]

Have been lurking for a while, preparing to obtain my basic ewuipment for the first batch.

Likely will target 5 gallon bottled, partial boil moving to full boil once I have a propane burner.

Many of the recilies I see call for a 6 or 7 gallon boil, allowing 1/2 gallon for evaporation.

Question: what is the minimum headspace to allow for in the primary? can a 7.5 gallon ale pail hold a 7 gallon net ferment? 6.5 gallon?

 

[Yooper]

I have some 7.9 gallon ale pales, and I usually do a 5.25-5.5 gallon batch. That's plenty of headspace, and I never need a blow off tube, just an airlock is fine. You might have trouble with anything bigger than a 5.25 gallon batch in a 6.5 gallon carboy, or 6 gallons in a 7.5 gallon bucket. It's not the end of the world- you can just intall a blow-off tube to prevent a mess- but I like to have plenty of headspace in primary.

 

[birvine]

I just brewed a 20 litre batch in a 30 litre carboy - everything contained.

B

 

[ultravista]

Are there any issues fermenting 5 gallons in a converted sanke keg? Is there such a thing as too much head space?

 

[Ace_Club]

Using a Sanke for 5 gallons should be fine. You're mainly worried about headspace in the secondary since CO2 production has dropped off significantly and can't adequately purge the headspace of O2.

 

[joeldp144]

I use the 6.5 gallon buckets from Northern Brewer, and they actually hold more than that.....7.5'ish. It probably is very dependent upon your brew gravity and yeast, but I typically use US-05 yeast, and I often have 6 gallons or so of wort.

I have never used a blow-off tube.....only air-locks. I don't worry about 6 gallon batches in my bucket.