Max Batch Size for 4 Gallon Water Jug?

[gavball6]

Anyone have an opinion on what the max batch size would be for a 4 Gallon Water Jug (#1 from Sam's Club... not trying to restart debates on using these as fermenters!)

I was thinking of trying to do a basic extract Kolsch recipe at a batch size of ~3.25 gallons. Does that seem right or do you think I could go bigger? Smaller?

Thanks!

 

[dkennedy]

That seems reasonable to me- figure a 6 gallon better bottle with a 5 gallon batch = head-space of 20% of the batch size. I would think that you could go for a 3.5 gallon batch, but would want to have a blow-off tube.

Hope this helps!

 

[gavball6]

I think I will try a 3.5 gal batch and see how it goes!