6 gallon recipe in 6.5 gallon fermenter

I have recently received the "plinian legacy double IPA extract" kit from northern brewer. After closely reading the instructions this ipa makes a 6 gallon batch to account for the amount of hops added.

My concern is a 6.5 gallon fermenter won't have enough room for the expansion during fermentation. I was wondering if a large blow off setup could work or if I should get a larger fermenter (and where to get this larger fermenter).

I currently have:
6.5 gallon ale pail
6.5 gallon big mouth
6 gallon pet better bottle
5 gallon big mouth

Taken directly from instructions on website:

REQUIREMENTS

"A 6 gallon glass carboy, with blowoff setup, to use as a
secondary fermenter—If you do not have a secondary
fermenter you may skip the secondary fermentation and add
an additional week to primary fermentation before bottling"


You'll be fine. No need for a larger fermenter.

How good is your temperature control during fermentation? Cooler fermentations go slower so you might not even need a blowoff but if you let the temperature get away from you, expect explosive fermentation. I'd probably use a blowoff tube and start the ferment just a few degrees below the yeast's preferred range to limit how fast they multiply and how fast they devour the sugars, then let it warm up slowly over the course of about 3 days. After the ferment seems to have stopped (it hasn't, it just looks that way) you can let the beer come to room temp without any problems.

If you have a three piece air lock you can use that on the bucket and attach a piece of tubing on the center "post" that you run into a growler with some star san in it. Or you could split it into two of your fermenters but that seems like a pain. There's an outside chance that you could use the bucket and standard air lock depending on how active a fermentation you're anticipating but the blow off configuration is pretty cheap insurance.

Todd

wapitiscat said:

If you have a three piece air lock you can use that on the bucket and attach a piece of tubing on the center "post" that you run into a growler with some star san in it. Or you could split it into two of your fermenters but that seems like a pain. There's an outside chance that you could use the bucket and standard air lock depending on how active a fermentation you're anticipating but the blow off configuration is pretty cheap insurance.



Todd

Click to expand...

I have used the 3 piece airlock method with the tubing plugged directly into the body of the airlock but have had clogs and nearly explosions before. Those were also 5 gallon batches in a 6.5 gallon carboy. I can perhaps use a 1/2" tubing blow off of my 6.5 gallon big Mouth bubbler but I'm just concerned about how much krausen and such will force its way out. I've been making very healthy yeast starters days in advance and have had wonderful, strong fermentation within just a few hours of pitching. This double ipa is probably the most complicated kit I've made and I just want to be prepared and know what to expect from my first larger volume brew.

It will be fine. I do a lot of five gallon batch's in five gallon carboys. Rig a tube and relax.

If you're using a traditional 6.5 gallon carboy use a 1" ID hose. They sell them at brew shops usually as "blowoff hoses".

That's a big beer and the krausen will be more than 0.5 gallons in volume. Don't risk a blowout - use the tube!

Alternatively, you could make up a smaller fermenter out of a 1 gallon jug and some blowoff hose. Even an old plastic applejuice container or something would work fine. Drill a hole in the top and slide the proper sized tube in. Make sure you don't drill the top too large, the tube should fit tight.

Another idea - why don't you just split the batch between your two big mouth bubblers putting ~3 gallons in each one.

Get the Blow off tube... I used to do that when I was fermenting my hefes and other active fermenters in smaller carboys.

You could also use a foam inhibitor, fermcap is one brand, however I am a little bit against that. Part of me secretly believes that it will also inhibit finished product head retention. This is completely unfounded, but my paranoia persists.

Found this thread as I have a similar situation. I typically brew 5 gallon batches but always end up with less than 5 gallons, so I've been adjusting my equipment setup and recipe amounts on BeerSmith and shooting for 6 gallons. Well, I must have my setup pretty dialed in now because yesterday I hit all my volumes and ended up with 6 gallons as planned. I used a blowoff tube connected to a standard three piece airlock and put the fermenter and blowoff container in a rope handled tub in the garage just in case it still makes a mess.

I couldn't bring myself to dump any wort and all my fermenters are being used so I couldn't split it. Woke up this morning to it chugging away, but we’ll see what it looks like when I get home from work.

You can get those 8.5 gallon buckets at the brew shops for like 14 bucks and make a blowoff tube with a mason jar or even just a pint glass with some sanitizer in it.