Using corny for primary?

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MrBJones

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Hello all. First post after some time away!

I'm considering using a corny keg for primary, looking for guidance and answers to some questions
  1. In general, are there an downsides?
  2. With a five gallon corny, is there any headspace above the five gallon level? (I typically do five gallon batches)
  3. Woud probably use a quick connect to attach a blowoff tube to the gas-in fitting. Is there a better approach for handling blowoff?
  4. Can priming sugar be added to a corny, and bottles filled straight from the keg?
  5. Is there anything to keep in mind regarding forced transfers with CO2?
  6. Rather than shorten the out tube, has anybody used the Clear Beer Draught System? If so, how did it work out? https://www.shop.clearbeerdraughtsystem.com/main.sc
  7. How difficult is it to clean/disinfect the keg and fittings between batches?
  8. What's the height of a corny, from the base up to top of the rubber collar? (needs to fit in my chest freezer)
  9. Is there anythig else I shoud be asking?:)
Thanks!
 
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In general, are there an downsides?

Yes, limited batch size.

With a five gallon corny, is there any headspace above the five gallon level? (I typically do five gallon batches)

Per measurements by @doug293cz, a corny has a volume between 5.3 and 5.35 gallons. So, very little headspace.

Can priming sugar be added to a corny, and bottles filled straight from the keg?

This would have the same issue as adding priming sugar to a carboy or any other primary... How would you mix the sugar evenly without stirring up trub? Also, you'd need to significantly shorten the dip tube to avoid pulling trub if you want to use it to transfer.

How difficult is it to clean/disinfect the keg and fittings between batches?

Kegs are not particularly hard to clean and sanitize. You do need to disassemble them though, which is a little more work than cleaning a carboy, for example.

What's the height of a corny, from the base up to top of the rubber collar? (needs to fit in my chest freezer)

Ball lock kegs are about 24.75" tall. Don't forget to add height for your airlock/blowoff/spunding valve.
 
I'll also add that harvesting yeast from a corny is a pain. And fermcap is helpful keeping krausen down so you can fit a bit more wort in there.
 
I do about 4.5g batches. I use both a cbds (2 kegs) and the janish filter (1 keg) in my beers. Sometimes I transfer beer to a second keg for serving but not always, makes it very easy. I’m not bottling tho if I were I’d add solution direct to bottle.

you need a filter to keep dry hops out, so the cbds with filter screen is

I use ball lock to starsan just as suggested. Sometimes I’ll pull it from my ferm chamber towards the end and cap with a spunding valve

I use ferm cap

the cbds tube will pick up dry hop aroma but I haven’t noticed this impacting my beers at all
 
I think MoreBeer made this keg just for this reason... otherwise i cannot for the life of me figure out why anyone would want a 6 gallon corny.
Is there any other reason?

For $110, you are like almost to a stainless bucket, and a good chunk of the way to an actual fermentor.

EDIT: duh! Of course! I got this email from moreber today.

"New 6G Ball Lock Torpedo Kegs!

When we say 6G we're not talking about some new cell towers, we're talking GALLONS! A lot of homebrewers brew their batches to finish around 5.5-6 gallons to account for loss along the way. Nothing hurts more than seeing beer start coming out the PRV and knowing you have another half gallon or so left in the fermenter! Not to mention if your carbing through the gas post you won't have much if any surface area for the cO2 if that keg is filled to the brim. Fret of wasted beer no More! with the new 6 Gallon Ball Lock Torpedo Kegs!"

https://www.morebeer.com/products/torpedo-ball-lock-keg-6-gal.html
 
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I was kinda wondering if there would be any chatter on the forum about these 6G kegs. I know that some of the less expensive stainless steel fermenters...or perhaps buckets don't handle pressure very well. So..if you're not interested in harvesting yeast, utilize a floating dip tube and ferment under pressure and/or conduct a transfer to another keg via pressure w/o issue?
 
I have to bump this on account of that torpedo 6 gallon corny. I’d love to be able to do pressure transfers as well as get a full 5 gallons of beer. Anyone have any experience with it for ferments? Headspace adequate for a full 5 gallon, vigorous ferment? I’d love to have a fancy spike conical or something but man…kegs are so simple and easy to clean and even this 6g keg, brand new, is nowhere near the $600+ it would cost for something fancy.
 
There is adequate headspace in a ball lock cornie. I get a full 5 gal plus 2+ pints easy. 3 pints and the gas tube is reached and the lid gets all in the beer when closing it up. I get a full 5 gal product fermenting in a standard cornie.

A blow off tube on the gas post will be just fine for ales and hefe. If it's a lager just spund it or use a low psi PRV and nothing should blow out.

Yeast harvest is incredible simple. Just burp the out post with a super short picnic tap into a small mason jar. After the first pint it's pretty clear.

A floating dip tube will be clear on the very first beer...but no yeast harvest possible until the keg is empty.
 
I thought about putting in some fermcap, but don't know how to use it so I didn't bother.

You just add it to the wort. Fermcap-S comes with some different labels (different re-packagers, I assume), but all the labels I've seen have the instructions front and center.
 
I am currently using a corny to ferment about 3.5 gallons of cyser. I use a gas fitting with a blow off tube. fermentation has slowed down, but as anybody who has worked with honey knows, it takes a long time for honey to ferment completely.
 
You just add it to the wort. Fermcap-S comes with some different labels (different re-packagers, I assume), but all the labels I've seen have the instructions front and center.

Mine didn't have any instructions...and I guess it is an off brand? "Foam Control Dropper 1oz" from Austinhomebrew.com

It doesn't have instructions...and when I looked at it...it looked like...super white and super slimy coagulated snot. My thoughts were..."Eww...I'm not putting that into my wort."
 
I'm using the Torpedo 6G keg for the first time, been fermenting for two days. Was able to put what I "think" was my anticipated 5.5G in, with some headspace. I thought about putting in some fermcap, but don't know how to use it so I didn't bother.
I think it might be a good thing that you didn’t use fermcap this first time. I’d bet you’re in the clear now if you haven’t had a blowout yet. Are you pleased with the torpedo? I think I’m gonna have to just get it. I love fermenting in kegs. I’ve only done 2.5 gallon batches in 5 gallon kegs though. I didn’t ever want to risk a full 5 gallons.
I am currently using a corny to ferment about 3.5 gallons of cyser. I use a gas fitting with a blow off tube. fermentation has slowed down, but as anybody who has worked with honey knows, it takes a long time for honey to ferment completely.
I am glad to see this because I have two separate 1 gallon batches of a traditional mead going and one of them has been fermenting for almost 3 weeks and still seems to be going. First time I ever tried mead. D47 yeast. Figured it was all good so I’m just letting it go.
 
I “tested” fermenting in a corny a couple of weeks ago with a cider. Dumped 4G of AJ, added brown sugar, and yeast and let it ride. Put 1G of mango nectar in a O2 purged keg, transferred from fermenter until the stuff looked kinda funky. Went super smooth, which is what led me to pull the buy for the torpedo keg.

I do however suspect I’ll have a blowout at some point. I’ve had my blow off tube get gunked up in a 7G fermonster. I just set aside a second one and have it ready to go “just in case”
 
I “tested” fermenting in a corny a couple of weeks ago with a cider. Dumped 4G of AJ, added brown sugar, and yeast and let it ride. Put 1G of mango nectar in a O2 purged keg, transferred from fermenter until the stuff looked kinda funky. Went super smooth, which is what led me to pull the buy for the torpedo keg.

I do however suspect I’ll have a blowout at some point. I’ve had my blow off tube get gunked up in a 7G fermonster. I just set aside a second one and have it ready to go “just in case”
I’ve had pretty bad blowouts even in a ss brew bucket. I am not necessarily afraid of a blowout, per se. With a keg it would nice to just hook a disconnect with a tube but those tiny parts in the gas post seem like they would just clog shut and it would be a nightmare. I know you can buy keg lids with air locks or remove the prv on one you have and rig something up. I just like the idea of popping off the disconnect when it’s finished and hooking up a tank for transfer.
 
I switched to fermenting all my IPA's in a corny and doing a closed transfer to the serving keg. I cut about 1.5" off the dip tube and put about 4.5 gallons of wort in there. Its been working great so far, a big improvement with my hoppy beers.
Don't worry about cutting off the dip tube, if you want to use the keg for serving, you can tilt the keg to get the last couple of pints out. You could also ferment/serve in the same keg if you wanted to. I had some issues with the keg sealing when I used a blow off tube, so I switched to a spunding valve.
For bottling off the keg, I suppose you could add a sugar solution to the keg, but the yeast will get all stirred up when you mix it in. Try the Domino dot sugar cube method and see if that works for you.
 
I switched to fermenting all my IPA's in a corny and doing a closed transfer to the serving keg. I cut about 1.5" off the dip tube and put about 4.5 gallons of wort in there. Its been working great so far, a big improvement with my hoppy beers.
Don't worry about cutting off the dip tube, if you want to use the keg for serving, you can tilt the keg to get the last couple of pints out. You could also ferment/serve in the same keg if you wanted to. I had some issues with the keg sealing when I used a blow off tube, so I switched to a spunding valve.
For bottling off the keg, I suppose you could add a sugar solution to the keg, but the yeast will get all stirred up when you mix it in. Try the Domino dot sugar cube method and see if that works for you.
I did the exact same thing. Cut the dip tube maybe an inch or so. I’ve only done a 2.5 gallon batch in that 5 gallon keg but I also opted to spund to maintain a few psi for transferring. I never thought about the lid not sealing right due to lack of pressure but that is a good point. I always put a bit of keg lube on the lid o ring just in case. I wasn’t concerned about the 2.5g batch blowing out so I spunded the whole time at a very very low pressure. My thought process for a bigger batch was always to let ferment with a blow off tube for a few days then after things settle a bit switch to spunding to keep some pressure for transferring. Does pressure from spunding also help keep krausen down:
 
I’ve had pretty bad blowouts even in a ss brew bucket. I am not necessarily afraid of a blowout, per se. With a keg it would nice to just hook a disconnect with a tube but those tiny parts in the gas post seem like they would just clog shut and it would be a nightmare. I know you can buy keg lids with air locks or remove the prv on one you have and rig something up. I just like the idea of popping off the disconnect when it’s finished and hooking up a tank for transfer.

Reading your post, I had a thought. I have extra floating dip tubes, and some of the filters too. Floating Dip Tube Filter Attachment | MoreBeer

What about hooking up a 'short' amount of tubing to the gas post and one of those filters? Thinking that should negate any clogging of the post from krausen, and still allow co2 out during ferment w/no danger of clogging, which would then also allow co2 in during transfer?
 
Reading your post, I had a thought. I have extra floating dip tubes, and some of the filters too. Floating Dip Tube Filter Attachment | MoreBeer

What about hooking up a 'short' amount of tubing to the gas post and one of those filters? Thinking that should negate any clogging of the post from krausen, and still allow co2 out during ferment w/no danger of clogging, which would then also allow co2 in during transfer?
That is an awesome idea. I just happen to have that filter sitting in my cart already. Maybe I’ll get a few of them and do what you suggested.
 
is that filter going in the keg or outside of it? I'd be careful of in the keg. The filter/tubing needs to be suspended such that it remains the headspace of the keg. if it is sitting in beer it will push beer out the same way that the out tube pushes beer out. Pressure builds, pushes on beer and out it comes the dip tube. Granted it will stop coming out when the beer falls below the filter, but it just seems like you'll either have to way underfill the keg to avoid the filter, or loose some beer.

I really dont think it is necessary. I think i started fermenting in cornies in 2017. I always use ferm cap, get 4.5-5 gallons in the keg (never weighed it) and i've only ever had yeast in my blow off twice. the second one is actively fermenting now. it has never clogged. Both times is was with A05 Voyager (an english strain that was a spring seasonal from imperial) and with OGS north of 1.060. when doing an OG south of 1.050 i had no blowoff whatsoever.

This one is actually a copitch of the A05 and Verdant. the A05 was a yeast cake from a previous english beer i did, but it was slow to take off and so i added a packet of Verdant the other day. can't say if the A05 finally woke up or the verdant took over, but either way, not worried about the clogging.
 
is that filter going in the keg or outside of it? I'd be careful of in the keg. The filter/tubing needs to be suspended such that it remains the headspace of the keg. if it is sitting in beer it will push beer out the same way that the out tube pushes beer out. Pressure builds, pushes on beer and out it comes the dip tube. Granted it will stop coming out when the beer falls below the filter, but it just seems like you'll either have to way underfill the keg to avoid the filter, or loose some beer.

I really dont think it is necessary. I think i started fermenting in cornies in 2017. I always use ferm cap, get 4.5-5 gallons in the keg (never weighed it) and i've only ever had yeast in my blow off twice. the second one is actively fermenting now. it has never clogged. Both times is was with A05 Voyager (an english strain that was a spring seasonal from imperial) and with OGS north of 1.060. when doing an OG south of 1.050 i had no blowoff whatsoever.

This one is actually a copitch of the A05 and Verdant. the A05 was a yeast cake from a previous english beer i did, but it was slow to take off and so i added a packet of Verdant the other day. can't say if the A05 finally woke up or the verdant took over, but either way, not worried about the clogging.

fair enough. I also have to ask, because I am spoiled by the thermowell in the brewtech, how do you deal with temp control? Just tape a probe to the side? I know NorCal has a keg lid with a thermowell welded on.
 
fair enough. I also have to ask, because I am spoiled by the thermowell in the brewtech, how do you deal with temp control? Just tape a probe to the side? I know NorCal has a keg lid with a thermowell welded on.
I have used one of the 6 gallon Torpedos as my fermenter for my last three brews. I have a wrap of Reflectix with Velcro on it. I just stick the probe between the wrap and the keg.
 
I switched to fermenting all my IPA's in a corny and doing a closed transfer to the serving keg. I cut about 1.5" off the dip tube and put about 4.5 gallons of wort in there. Its been working great so far, a big improvement with my hoppy beers.
Don't worry about cutting off the dip tube, if you want to use the keg for serving, you can tilt the keg to get the last couple of pints out. You could also ferment/serve in the same keg if you wanted to. I had some issues with the keg sealing when I used a blow off tube, so I switched to a spunding valve.
For bottling off the keg, I suppose you could add a sugar solution to the keg, but the yeast will get all stirred up when you mix it in. Try the Domino dot sugar cube method and see if that works for you.
How are you getting your hop into the keg for IPAs?
 
In addition to other comments, YES, the Clear Beer Draught System is awesome for fermenting in kegs, especially if you plan to dry hop and use the one with the screen. But, yeah, getting 5 gallons of finished beer isn't really possible is a big down side. But it's definitely the way to go for anything smaller, like 2.5 or 3 gallon batches.
 
is that filter going in the keg or outside of it? I'd be careful of in the keg. The filter/tubing needs to be suspended such that it remains the headspace of the keg. if it is sitting in beer it will push beer out the same way that the out tube pushes beer out. Pressure builds, pushes on beer and out it comes the dip tube. Granted it will stop coming out when the beer falls below the filter, but it just seems like you'll either have to way underfill the keg to avoid the filter, or loose some beer.

I really dont think it is necessary. I think i started fermenting in cornies in 2017. I always use ferm cap, get 4.5-5 gallons in the keg (never weighed it) and i've only ever had yeast in my blow off twice. the second one is actively fermenting now. it has never clogged. Both times is was with A05 Voyager (an english strain that was a spring seasonal from imperial) and with OGS north of 1.060. when doing an OG south of 1.050 i had no blowoff whatsoever.

This one is actually a copitch of the A05 and Verdant. the A05 was a yeast cake from a previous english beer i did, but it was slow to take off and so i added a packet of Verdant the other day. can't say if the A05 finally woke up or the verdant took over, but either way, not worried about the clogging.

Good points. This was the ridiculous ferment that went crazy in my Fermonster (K97). I had hooked up my star san filled keg pretty early, so a lot of that gunk ended up in the star san itself, so after that...I decided to wait a little longer in the ferment process before starting a keg purge. Gave it a good cold crash before transfer, no problems.

f48cf367-614b-468a-84d7-e289517c3c46-jpeg.728423
 
Sorry, I gave bad info earlier. A ball lock corny will hold 5.5 gallons total "usable" volume and still be able to work the lid and a short gas tube not submerged.

Fermenting in Corny Keg

Here is my post on another thread where I measured the volume.
 
How are you getting your hop into the keg for IPAs?

seems I forgot to reply. I hook up gas and flow at a couple psi. Pull the prv and turn 90 so it stays open then push the top in. Dump in hops. Close lid, retune prv to normal, increase pressure to 20 or so and purge a few times. Repeat for ddh. Sometimes will transfer to dry hop keg sometimes I dump right into fermentation keg.In both cases that dry hop keg becomes my serving keg.

When I first started doing Star San purges I would purge keg then dump hops into keg using the same flow process but now I transfer beer first, as it reduces the air volume significantly

also, here’s a photo of that copitched verdant and voyager WITH ferm cap. It seems it was no match for when the voyager woke up. That’s quite the film of yeast and Star San sitting there.
 

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I think it might be a good thing that you didn’t use fermcap this first time. I’d bet you’re in the clear now if you haven’t had a blowout yet. Are you pleased with the torpedo? I think I’m gonna have to just get it. I love fermenting in kegs. I’ve only done 2.5 gallon batches in 5 gallon kegs though. I didn’t ever want to risk a full 5 gallons.

I am glad to see this because I have two separate 1 gallon batches of a traditional mead going and one of them has been fermenting for almost 3 weeks and still seems to be going. First time I ever tried mead. D47 yeast. Figured it was all good so I’m just letting it go.
So far the recipe has been about 3 1/2 gallons of apple juice, I pound of corn sugar and a cinnamon stick. This brought the gravity to about 1.060. I then added 4 pounds of honey in 2 stages, with about a week in between. The whole thing has fermented down to a bit less than 1, having not seen bubbles for a few days. Just put it in the fridge to cold crash, and gelatin to fine it.
I tasted the result and there is definitely some alcoholic heat, my calculations show about 15 percent alcohol or better, though I hope the heat mellows with time.
 
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So far the recipe has been about 3 1/2 gallons of apple juice, I pound of corn sugar and a cinnamon stick. This brought the gravity to about 1.060. I then added 4 pounds of honey in 2 stages, with about a week in between. The whole thing has fermented down to a bit less than 1, having not seen bubbles for a few days. Just put it in the fridge to cold crash, and gelatin to fine it.
I tasted the result and there is definitely some alcoholic heat, my calculations show about 15 percent alcohol or better, though I hope the heat mellows with time.
15% sounds like a heavy hit. Are you planning on aging it for a while or were you getting a head start on some winter sippins?
 
Lately, I've been fermenting and serving almost all my beers from corny kegs. Less chance for oxygen ingress, and less vessels to clean which is great because I can be lazy. All my batches are 4 gallons or less so I have no worries about headspace.
 
Also adventures in home brewing sells loose handled ball lock kegs for $29 plug shipping. Ive bent all of my dip tubes up to the sidewall, pours only 1 or 2 yeasty pints and then clear. Only thing that is a drag is shipping ends up costing 1 keg - i think for just under $100 i get 3 shipped to Cali.

parts you have to replace, O-rings and i use universal poppets because sometimes they are thrashed.
 
for a 10 gallon, you could prob do 8-9 gallons. def 9 if you use femcap and keep under pressure
I was thinking of getting the 6 gallon for 5 gallon batches but saw that 10 gallon for a little more money and would give me plenty of headspace. Just wondering if I’m too concerned about it and should stick with that 6 gallon.
 
I was thinking of getting the 6 gallon for 5 gallon batches but saw that 10 gallon for a little more money and would give me plenty of headspace. Just wondering if I’m too concerned about it and should stick with that 6 gallon.
Yeah- why not get the 10 gallon for a few more bucks. Might be worth it down the line. Wether you use a 5,6, or 10 gallon keg- make sure it is properly cleaned, sanitized, etc.
 
I was thinking of getting the 6 gallon for 5 gallon batches but saw that 10 gallon for a little more money and would give me plenty of headspace. Just wondering if I’m too concerned about it and should stick with that 6 gallon.

While I haven't measured to see how accurate the markers are on my Foundry, I suspect that can't be ridiculously off. I say that because I had 6 gallons ready to transfer into my Torpedo 6G and did so and had 3L of crud that I didn't. I did put some Fermcap in there when I pitched the yeast and hooked up a blowoff tube. Never saw any gunk get up into the tube.

My biggest frustration is that I've had to tilt the damn thing when racking to keg. 1st time it only finished about 1/2 on its own (and that damn thing is heavy to hold there when half full), this last transfer which was last night got about 75% through. If that is as good as it gets...I guess I'll take it but I cut the stupid tube length to just reach past the hump at the bottom, and have a filter on it at the lowest setting.
 
While I haven't measured to see how accurate the markers are on my Foundry, I suspect that can't be ridiculously off. I say that because I had 6 gallons ready to transfer into my Torpedo 6G and did so and had 3L of crud that I didn't. I did put some Fermcap in there when I pitched the yeast and hooked up a blowoff tube. Never saw any gunk get up into the tube.

My biggest frustration is that I've had to tilt the damn thing when racking to keg. 1st time it only finished about 1/2 on its own (and that damn thing is heavy to hold there when half full), this last transfer which was last night got about 75% through. If that is as good as it gets...I guess I'll take it but I cut the stupid tube length to just reach past the hump at the bottom, and have a filter on it at the lowest setting.
I have a flotit 2.0 on order. I’m hoping that will replace cutting dip tubes. I’m also hoping to avoid having to use fermcap, although it’s always there if I need it. My fear with the 6 gallon is not having enough headspace. I’m leaning toward getting a 10 gallon.
 
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