Size matters??? Carboy question...

[BubbaMan]

Hello friends,

A local seller is offering used 5 and 6 gallon carboys. My choice, $20 ea.

I think I'll buy a couple and I want to know if a 6 gallon carboy would work for secondary fermenting of 5 gallon batches. This is my main use for carboys. Would I have oxidation issues?

I probably will not use glass for primary fermentation, plan on using a plastic bucket fermenter for that.

So, should I buy the 6 gallons or just buy the 5 gallon ones?

Thanks!

 

[Mainer]

I usually go the other way. I use 6 gallon carboys for primary and 5 gallon carboys if I'm doing secondary. I do it that way because primary needs extra headspace for fermentation, but you don't get that kind of krausen in secondary, so the 5 gallon carboy helps eliminate oxygen contact.

Edit: unless you're doing substantial dry hopping or adding fruit in secondary or something. Then the 6-gallon might come in handy.

 

[dyqik]

Are you aiming to put exactly 5 gallons into a keg after secondary? If so, you'll want 6 gallon carboys, as you'll likely be leaving some trub behind when transferring.

BTW, the only real reason I can think of for using a secondary is for dry hopping (and even then I don't think a secondary is a good idea), oaking or sitting on fruit, or a secondary brett or lacto fermentation. In all cases, you'll want to leave something behind when transferring out, which means you want to put more than 5 gallons in the carboy to get 5 gallons out.

 

[Mainer]

Are you aiming to put exactly 5 gallons into a keg after secondary? If so, you'll want 6 gallon carboys, as you'll likely be leaving some trub behind when transferring.

BTW, the only real reason I can think of for using a secondary is for dry hopping (and even then I don't think a secondary is a good idea), oaking or sitting on fruit, or a secondary brett or lacto fermentation. In all cases, you'll want to leave something behind when transferring out, which means you want to put more than 5 gallons in the carboy to get 5 gallons out.

I rack all my lagers to secondary to get them off the trub for the long lagering phase. I find you get a cleaner profile that way.

 

[BubbaMan]

I usually go the other way. I use 6 gallon carboys for primary and 5 gallon carboys if I'm doing secondary. I do it that way because primary needs extra headspace for fermentation, but you don't get that kind of krausen in secondary, so the 5 gallon carboy helps eliminate oxygen contact.

Edit: unless you're doing substantial dry hopping or adding fruit in secondary or something. Then the 6-gallon might come in handy.

I will probably do some dry hopping for IPA's, but was not planning to use secondary fermentation for ales. I suppose really the 5 gallon carboys will serve my needs, which is to lager 5 gallon batches for my FIL, who drinks lagers and pilseners.

Are you aiming to put exactly 5 gallons into a keg after secondary? If so, you'll want 6 gallon carboys, as you'll likely be leaving some trub behind when transferring.

BTW, the only real reason I can think of for using a secondary is for dry hopping (and even then I don't think a secondary is a good idea), oaking or sitting on fruit, or a secondary brett or lacto fermentation. In all cases, you'll want to leave something behind when transferring out, which means you want to put more than 5 gallons in the carboy to get 5 gallons out.

As I mentioned above, my plan is to use secondary fermentation ONLY for cold lagering 5 gallon lagers and pilseners for my FIL. My thought was to use primary fermentation only when making the IPA's, stouts and porters that I'll brew for myself.

All advice is appreciated, so feel free to correct me if my thinking is wrong...and thanks for your responses!

 

[LLBeanJ]

I'd go with the 5 gallon for secondary, as you will want the beer level to rise all the way up to the neck. Leaving a gallon of headspace in secondary is asking for infection and oxidation problems.

 

[dyqik]

For lagering, yes, a 5 gallon carboy makes sense for a 5 gallon batch. Personally I rarely lager, and if I do, it's in a corny, so that didn't occur immediately to me.

 

[kh54s10]

For secondary you want a little headspace as possible.

Even when I do lagers I don't do a secondary. 2 weeks fermentation 2 days rest 2 weeks ramp down for lager - keg it and leave it another couple of weeks before tapping the keg.

 

[brandonlovesbeer]

You can never have enough larger car boys. I only have one 6.5gal and the rest are 5gal. Ugh. I want more bigger ones so I can do more batches at a time. I have to split any additional batches among all the small carboys so they don't blow out.

 

[brandonlovesbeer]

But honestly if he's offering you all these carboys then just get a bunch of both.

 

[IslandLizard]

Just be extremely careful when handling carboys, OK?

After all, they are huge glass jugs of unknown quality and thickness, and can cause very serious injuries when they crack.

I only use them for aging sours, so handling is minimal. But still...