Is a 6 gallon carboy too big

[tigerdentist]

for secondary "fermentation" of a 5 gallon batch? Is the excess air going to have a chance to oxidize the beer? Is a 5 gallon carboy better or needed?

 

[Milhouse]

I suggest a 5 gallon carboy for secondary. The less air space, the better.

 

[Tech211]

If I didn't have a five gallon carboy, I'd seriously consider leaving it in the primary unless there was a compelling reason to move it (e.g. dry hopping, fruit, oak).

 

[dagamore]

you can put it in to the 6gal and then use clean/sanitized marbles to take up space, I know wine makers do this often.

 

[Tech211]

That's a neat idea. How do you rack the bottom portion of liquid, though?

 

[Yooper]

That's a neat idea. How do you rack the bottom portion of liquid, though?

A 6 gallon carboy is fine for a secondary for beer.

You rack the same way you always do. I start with my siphon tip in the middle of the carboy, and lower it until it's above the trub. You can see it, so it's not a problem racking from a carboy.

I have used the marble trick in wine- but it takes hundreds of marbles to make up a gallon. You may not want to do that for your beer.