Question on Secondary Fermenter Container Size for 5 Gallon Batch

[beerandguitars]

I am starting my next beer soon and will use all glass carboys for primary and secondary fermentation. I am wondering if you need to use a 5 gallon container/carboy for your secondary, or if you can get by with a 6 or 6.5 gallon container/carboy?

I've heard you need to use 5 gallon so that there is as little air as possible. Is this true?

Thanks for your help.

 

[Ridire]

Look at the "Quick Question About Oxidation" thread right below this one.

 

[woozy]

"need" is a relative term. But, yes, you *want* to minimize headroom so yes, this is a concern that many take quite seriously to the extent of finding the headroom of a 6.5 gallon carboy unsuitable for secondary conditioning.

 

[Johnnyhamer]

If you plan on adding fruit or anything that may restart a fermentation don't use a 5 gallon.