Primary filling in carboy about 1/3 okay?

[Sol_Om_On]

I was wondering, is there a minimum carboy fill-up limit for primary? Is it for example problem free to fill a carboy with primary only up to 1/3 of the full carboy?

I know that I should fill it up to the neck for secondary, but I'm thinking that perhaps during primary so much carbon dioxide is produced that it doesn't matter how much or little I fill up the carboy.

Thanks :fro:

 

[ACbrewer]

On a primary? depends on what you are worried about I suppose. As far as 'how much co2' does this produce, one of these threads has it, but the math works out to a gravity of about 1.040 will produce 60 volumes of CO2 ... meaning if you have 1 gallon you will off gas about 60 gallons of co2. So if your concern is later oxidation. That won't be a problem.

if your concern is dust in the air, well obviously less is better, but give it a good pitch.

 

[Newsman]

Yeah, I'm no expert, but I think you're pretty good.

 

[mtnagel]

Yeah that would be fine.

I've done 2.5 gal in 6 gal bucket before with no issues.

For 1 gal batches I have a 2 gal bucket. I could probably do 1 gal in a 6 gal bucket, but that just seems crazy.

 

[Sol_Om_On]

Thanks for your fast and great help everyone, this forum so reliable it's ridiculous