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Old 02-12-2010, 05:21 PM   #1
Oct 2009
Tonawanda, Ny
Posts: 56

I have read a few articles lately about using 5.5 gal corny keg as a primary fermenter with a little modification. Dose anyone have any experience with this or have any advice or pros and cons? Let me know Thanks all.....

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Old 02-12-2010, 06:29 PM   #2
Mar 2009
Buffalo, NY
Posts: 987
Liked 18 Times on 16 Posts

I use one for secondary a lot. I just went to keggle brewing and bought a replacment fermenting lid for it. works great and preserves the original lid for kegging. I'd be worried about head space. Make sure you use a blow off tube.

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Old 02-12-2010, 07:37 PM   #3
Aug 2008
Portland OR
Posts: 5,387
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The normal corny keg is 5 gallons, keep that in mind when doing your brewing. It works very well. If you are going to do 5 gallon batches look for a 10 gallon corny as it will make it much easier. I use a 15 gallon keg for 10+ gallon batches and love how easy it is to transfer to serving kegs when done & cold crashed.

con= If you are a fermentation watcher there will be nothing to see with this method.
I really have no issues with doing it this way and only positives like the CO2 push transfer. Clean up is pretty easy, no glass, no plastic just Stainless Steel.

Buying the extra lid is not needed. You can rig up your airlock to the gas in post with a QD, some tubing and hose clamp. Or you could remove the pressure relief valve from the lid and fit some tubing over that hole with an airlock attached.

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Old 02-13-2010, 01:21 AM   #4
May 2009
Santa Clara, CA
Posts: 49
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I have used cornies to ferment in using gas QDs with the tube linking to airlocks, make sure those gas connections are set properly. One of mine didn't engage the poppet properly and pressurized the corny pretty quickly. the pressure relief valve kicked in though and prevented any major problems.

All that said, I'm still not sure I will continue fermenting in kegs, as I get a lot of trub going into the serving keg when i transfer, even after blowing off 2 or 3 glasses worth to try to clear the space around the dip tube.
Brewery name goes here...

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Old 02-13-2010, 01:45 PM   #5
cyberbackpacker's Avatar
Jul 2008
Holland, Michigan
Posts: 1,481
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I use them exclusively with great success; you can ferment under pressure (there is a thread on here "how to") or do like already mentioned and rig up an airlock to a piece of tubing off of one of your ball lock disconnects.

I have a batch of ordinary bitters fermenting right now, and I got 4.75g into the fermenter. I normally shoot for 4.25-4.5g batches, but got a bit higher efficiency than expected.

When I have this large a batch I use fermcap-s and have yet to experience any problems (this latest batch my latest testament).

My dip tubes are not bent or cut-- I use them as is. I get hardly any sediment/trub when I transfer (under pressure) to my serving keg. However I do a long cold crash, which really helps to compact the trub.

There are a few really good threads on this on here... check at the bottom of the page to "related links".

Good luck. I highly recommend using them in this way; I strongly believe in having multi-use over single use pieces of equipment. Multi-use, ferment under pressure if desired, transfer under pressure, stainless steel, cost is comparable to better bottles (I got mine cheaper).

Only downside, is you cannot see inside. That is it.


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Old 02-13-2010, 02:04 PM   #6
Edcculus's Avatar
Jun 2007
Greenville, SC
Posts: 4,546
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I've done a few batches in cornys, but haven't gone to full transferring under pressure. No need to modify a lid. Just take off the gas post and slide on some sanitized tubing. Run that down into a jug of starsan. Blowoff tubes are much easier than airlocks, esp for primaries.

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Old 02-13-2010, 04:02 PM   #7
Hugh_Jass's Avatar
Nov 2008
Posts: 1,981
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Jumper from primary keg to secondary/serving keg

Blow-off air lock inserted into pitcher of Star-San

10 gallon in temp controlled freezer.

I've fermented ~150 gallon in corneys with great success. I slightly bend the dip tube and cold crash to compact the trub. From the time the beer is inocculated to the time it hits my glass, it never sees oxygen.

Any questions, please ask.
"My new company is going to sell Aqua-infused(tm), Alphabetamashed(tm), Wortboiled(tm), Multihops Brewed(tm), Saccharomented(tm), Lageriffic(tm) beer. - Bobby_M
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Old 02-14-2010, 04:59 PM   #8
Jan 2008
Drain, OR
Posts: 605
Liked 7 Times on 6 Posts

I've done appfelwein in corneys. I run a tube off a gas quick disconnect to an airlock. I server from the same keg. Super convenient. Only problem I have is it takes 4-5 pints to kick out all the yeast. I haven't done anything to my dip tubes, but I'm considering bending it up a bit next time I have it empty and open.
How I brew: Stir plate starters, Extract, Full boil in a Keggle, 10 gallon batches.
Brewing upgrades in progress: temp controlled ferment, stir plate re-work, building mash tun, milling station

Planned House Ales: an Amber, an IPA, a dark IPA, a Mango Ale, a blueberry oatmeal stout, a dry Irish stout, a honey wheat, Apfelwien

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Old 02-15-2010, 02:48 AM   #9
DarkSide's Avatar
Feb 2009
Barrie, Ontario
Posts: 71
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I switched to using corny kegs as fermenters last year, when I finally completed my all-grain setup. I found there to be many benefits to using the kegs as apposed to the usual glass carboys, which is what I used before.

The stainless steel interior of the kegs as well as the large opening made for easy cleaning and sanitizing. I don't miss the days of soaking and scrubbing the glass carboys, especially the top, where trying to use a carboy brush to scrub the bottom and top of the carboy was always a chore.

Some other posts that I had read mentioned being worried about excessive blow off or pressure during the initial fermentation. So I purchased a special lid that allowed me to attach a proper blowoff tube.

Also, since oxygen is a concern once fermentation has started, I found using the keg was the perfect way to keep the oxygen away from the beer. I use a CO2 tank to pressurize the primary and then transfer the beer to the secondary keg when the time is right. At bottling time I use the same process with the CO2 tank to then move the beer to my bottling bucket.

For more info on how I converted my corny and pics, check out my original post about my fermenter....

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Old 02-15-2010, 03:08 AM   #10
OntarioBeerKegs's Avatar
Apr 2009
Mitchell, Ontario
Posts: 537
Liked 42 Times on 31 Posts

I remove the liquid out post and attach a hose with a hose clamp to the threads. Plenty of room for my blow off and do not need to buy extra connects or lids.

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