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How much room for fermentation

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JWWard03

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Hi all. I got a 5 gallon food grade bucket from Lowes for my fermentation bucket. 5 gallons of liquid puts it about an inch below the lid. How much "breathing" room does the fermentation process need above the liquid line? Can I just split into two buckets of 2 1/2 gallons each and split the yeast between the two and expect good results? Is it ok just to put 4 1/2 gallons in for the fermentation? I'm brewing an American Ale from Northern Brewery. I couldn't find any bigger buckets locally.
 

apache_brew

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4.5 gallons should be ok. The headspace you need is primarily to support the krausen. I’d just stick with one bucket for however much wort you can fit in there. If you have a gallon of wort left over, use something else like a 1 gallon glass jug if you have it and divide the yeast proportionately. The name of the game is minimizing headspace needed and in turn minimizing the number of vessels to lessen the chance of contamination and maximizing your volume of delicious end product.

If you have a 3 piece airlock, it’s really easy to stick a piece of transfer tubing into the airlock and then turn that down into a jar of Star san. This would be a simple blowoff tube for the early stages of fermentation if your worried about a vigorous krausen foaming over. Once fermentation calms down, pull the tube and drop the airlock pieces back onto the airlock.
 

shoengine

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Hmm, if minimizing headspace is the game, I'm screwed with my 8gal fermentor!

When I was using smaller fermentors I had issues a couple of times with "bubble-overs", but as long as I kept around a gallon free, I never had issues with vigorous ferments.
 

Immocles

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Leaving only an inch is going to definitely want a blow off tube. I regularly ferment 3Gallons inside of a 3G fermonster and it requires a blow off every time. I just leave the blow off attached until I package or until I dry hop (if I am). 4.5G would still be tight, I think, and I would still put a blow off on that volume.
If you do choose to split it between two batches, I suggest to NOT dry hop those batches if you had that in mind. Its too large of a headspace.
 

ncbrewer

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I use a 7.9 gallon bucket for 5 gallon batches. I like it because I've had problems with a blow-off tube. I had hops in the fermenter - they plugged the blow-off tube and made a big mess. By using a larger fermenter, I no longer have blow-offs. So for your case, I would lean toward two 5 gallon buckets or a single 7.9 gallon bucket. (Note: I don't do high gravity brews, and I control fermentation temperature. Otherwise, you might get a blow-off even with a larger fermenter.)
 

bu_gee

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I don't understand the head room thing either, that is, there being too much. Eventually the CO2 from the fermentation will purge it out and everything will be fine. I did the math a long time ago so I might misremember, but a 5-gallon batch of 1.050 OG wort should produce about 200 L of CO2 by the time it is done fermenting.

I generally try to keep about 15-20% of the chamber for headroom but, as usual, there are lots of factors at play here including the OG of your beer, the yeast strain, temperature, shape of the container, the local gravity anomaly, etc. that are more meaningful than any generalizations that any of us could make.

That being said, I'm going to ignore my previous paragraph, and say that 2 1/2 gallon /should/ be safe, but I'd feel pretty anxious about 4 1/2 gallons without a blow-off tube. The 15-20% number from above would leave you at 4-4.25 gal.

Good luck!
 
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JWWard03

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I'll just get the wort prepped and into the bucket and siphon 2 gallons into the Mr Beer mini-keg before putting the yeast to work. I'm not comfortable setting up a blow-off tube this early in my learning. I ordered some Star San that should be here Wednesday and then I'll get started. Thanks for the advice.
 

Sacha

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Just blew my airlock off for the first time last night while making 5 gallons in a 6.5 gallon fermenter. I'd go for a blow off tube regardless of volume.
 

Birrofilo

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I think the common practice is to fill the carboy 3/4 of the volume, but you can fill it more (near the brim) if you use an anti-foaming agent. White has a paragraph on it in his book on Yeast, and he recommends anti-foaming agents, they reportedly do not affect the quality of the beer.
 
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JWWard03

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I ended up finding a 6 gallon bucket I can use. It's meant for baseballs, but it should work and the lid is tight.
 

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Birrofilo

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@JWWard03

Did you check for the "food safe" symbol? Not all plastic buckets are created equal. Even within the same material (PP, PET etc.) there are differences between different plastics, and not all are suitable for food.
 
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JWWard03

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It has the PP symbol on the bottom and is also not colored or dyed inside so I'm going with it. Found this while researching.

Polypropylene (PP)
Polypropylene is a widely used plastic. You likely have polypropylene plastic in your fridge and cupboards right now: it’s regularly used in reusable food storage containers. It’s also the resin used to make yogurt containers and other single-serving tubs.

PP plastics are approved for food contact. They are inert materials and do not present a health hazard to the consumers. The FDA began to approve recycled polypropylene as food-safe in 2013.

Polypropylene’s high melting point makes it suitable for microwaveable food containers. It’s nonvolatile and doesn’t react to liquids, acids, or bases, so it’s perfect to store a wide variety of foods.
 
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JWWard03

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It's tight, but not air tight. 've got some 3 piece air locks and will be putting one on there today. There's a foam layer to the lid that I've got to deal with but I think that'll work as extra sealing material in addition to the grommet that came with the air lock. I'll post pics when I'm done. This will be my first non-Mr. Beer brew and I'm getting nervous.
 
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JWWard03

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I'm brewing a Block Party Amber Ale from Northern Brewery. Should I be worried about a blowoff tube? I have two 5 gallon buckets I can split the wort into if that's something I should be thinking about. Wasn't sure if an amber ale is a big foam producer. There's a good 5 inches above the 5 gal mark before the lid.
 

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McKnuckle

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I don't think you need to worry about exceeding the headspace in that bucket during fermentation. But tubing for a blow-off is good to have in your toolkit, so you should get some anyway. If you use tubing with wide enough ID to fit over the stem inside your airlock, you're all set. I think that's 3/8" or 1/2", can't recall - just measure. You'd run that into a jar of sanitizer.
 
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JWWard03

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Thanks. Got to be 1/2 inch because my 3/8 tube is the same size.
 

odie

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I think the typical fermenter bucket is 6-6.5 gal. Kinda pricey compared to a 5 gal but it's what you really need. Two 5 gal buckets is cheaper but takes more space.
 
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JWWard03

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I think the typical fermenter bucket is 6-6.5 gal. Kinda pricey compared to a 5 gal but it's what you really need. Two 5 gal buckets is cheaper but takes more space.
Found my 6 gallon bucket for $17. We are a baseball family so having a Rawlings bucket just fits.
 

V-Fib

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As long as the bucket was smooth and sanitized on the inside you should be good. A lot of the things with the PP food grade label just mean its PP with no added dyes.

But I would highly recommend getting set up to use blow off tubes. That way you can get about 5.5 gallons in the bucket to account for the trub loss at the end of fermentation and end up with a solid 5 gallons of beer. For me the blow off tubes add a layer of peace of mind.
 

odie

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I wonder why homebrewing isn't based upon 4 gal batches? The 5 gal bucket is pretty universal. Home brewing was probably well entrenched before the 5 gal corny kegs came into common use. Or has kegging been used for long enough to see all the recipes gravitate to the 5 gal standard?
 
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