Sanity Check: Keg vs Fermzilla

[mashdar]

TL;DR: For pressure fermentation, is there any reason other than price to consider a fermzilla over a 10 gallon torpedo keg?

I'm still in the process of upgrading my gear, having recently come back to the hobby. My next upgrade will probably be a pressure fermentation vessel. The obvious default seems to be a 10 gallon keg, but I've been impressed with Kegland for cost effective gear, so I was weighing pros/cons of a fermzilla. I don't really need a connical bottom, so default would be the ~ 7gal all-rounder.

Can anyone think of more reasons to consider a plastic fermenter?

Pros:
+ price (currently ~$90USD vs $220USD)
+ clear, can see what's happening
+ nonconductive, might get better pill signal
+ marginally lighter weight

Cons:
- vulnerable to scratching
- annual hydro testing (*)
- clear (hop skunk risk?)
- harder to use for serving (double duty)
- O2 permiability (mostly lid interface)
- requires stand
- more gaskets
- temperature sensitive
- more fragile posts etc

Anyone have anything compelling to add? Visibility is nice, but I'm leaning towards a 10gal torpedo keg. (Or maybe 15gal since it's only $20 more?)

*I actually couldn't find much about hydro test schedule on kegs. Anyone know? If the only pressure source is a regulator at <1/3 vessel rating, it's pretty low risk, but an uncontrolled fermentation seems iffier.

 

[Broken Crow]

I've got a gen 1 14.5G Fermzilla and I love it. I'm biased owing to disability so.. Very much like to have something even I can pick up handle easily with one hand (Unlike my sanke-fermentor) A 10G Torpedo sure, but do you really need all that extra headspace? My 14.5 can easily deal with a 12G batch and I'm comforable with the head room, though I do want a 7.9G All-Rounder for smaller batches. As to the first 4 of your "Cons";
- vulnerable to scratching - Be careful.
- annual hydro testing (*) - Blow that...worry about it when it fails in however many years.
- clear (hop skunk risk?) - Don't keep it in the sun or use flourescent light around it, or just throw a cloth over it.
- harder to use for serving (double duty) - Depends on your kegerator or keezer size...plus; you'll be able to see when it's about to pour cloudy from the bottom... I just keg from it, nicely closed-loop.
All that said; In the long run I don't like the sometimes difficult valve and dump bottom, and will at some point replace it with an All-Rounder.

 

[mashdar]

but do you really need all that extra headspace?

It might avoid need for blowoff on 3787? (maybe? lol... I think I overflowed a 6 gallon carboy with 3 gallons of Belgian quad one time) edit: And I sometimes do 7gal batches for various reasons.

- annual hydro testing (*) - Blow that...worry about it when it fails in however many years.

My concern is for safety - I don't know what the typical mode of failure is for something like this, but almost 8 gallons with a 35psi prv is a pretty big bang. Granted a lot of that would be liquid, hopefully (less stored energy). I don't mess around when it comes to pressure vessels.

 

[AlexKay]

You've pretty much got it, I think. It's hard to beat a keg as a fermentation vessel. Plug for a FlotIt for your keg-fermenting needs.

 

[hiphoppotamuss]

I love my gen 2 fermzilla but also love the ease of keg fermenting.

A big pro for me is the ability to dry hop oxygen free. I have three receptacles and when it’s time to dry hop, I just fill a second with the hops, close the valve, unscrew the used receptacle, attach the new, purge with CO2 and voila!

O2 free transfers are also super easy although I imagine one could do this with a keg as well.

A big con is, despite all the lube in the world, disassembly is a massive chore. Just a huge pain and despite 15 or so batches in my fermzilla, I haven’t found a way to make this any easier.

 

[redrocker652002]

I have been thinking about fermenting in a corny. I have 5 clean and ready to go. I might try it with my next batch to see. I like the idea of hooking it up, putting another keg in line to be able to transfer pretty easily. The dry hop part has me a bit worried, as you have to open the second keg to add the hops before transfer. Unless I can add the hop pellets during the initial fermentation and let them sit in the second keg for a week or so. That would probably add O2 into the mix, which I am trying to avoid.

 

[Broken Crow]

My concern is for safety - I don't know what the typical mode of failure is for something like this, but almost 8 gallons with a 35psi prv is a pretty big bang. Granted a lot of that would be liquid, hopefully (less stored energy). I don't mess around when it comes to pressure vessels.

Ok, I was kinda blase about that, but Yeah: Safety First... I know damn well that even at 15psi a burst vessel can be dangerous and messy, but I'm reasonably confident in the cheap Kegalnd spunding valve, not for their accuracy but for their cheapness in that they'll fail before the body of the Fremzilla does, so I know I'll always have a reasonable layer of protectction once its plugged in.

 

[Broken Crow]

Oh forgot to say; Yeah I am biased by the ease of handling owing to disability, but even I use a sanke for my longer term fermentations. Personally, I'm happy to have both, but if I had to choose only one, It'd be an All-Rounder owing to my medical bias.

 

[Wayne1]

You may want to take a look at Clawhammer Supply 6.5 gallon Stainless Keg Fermenter

 

[Grizwold1]

dry hop part has me a bit worried, as you have to open the second keg to add the hops before transfer.

My last two brews I have put dry hops in a mesh bag, and put it into a sanitized and dry corny keg. I purge this keg and an eventual serving keg with fermentation gas with the dry hop already in place. One week in I transfer to the dry hop keg and finish the ferment. Then transfer to the serve keg--all pretty close to oxygen-free. Seems to be working so far. (Any critiques/suggestions for improvement would be appreciated appreciated!!)
edit: one minor downside is that means an extra keg to clean and sanitize, but I'm OK with that.

 

[mashdar]

I just fill a second with the hops, close the valve, unscrew the used receptacle, attach the new, purge with CO2 and voila!

Do you leave the bottom valve open at the start of fermentation? I may have a flawed view of how people use the fermzilla.

 

[mashdar]

You may want to take a look at Clawhammer Supply 6.5 gallon Stainless Keg Fermenter

That does look neat. The thermowell is a nice touch.

I feel like TC is a money hole I've been respectfully keeping at a distace. Gotta finish the college funds, first. : )

 

[hiphoppotamuss]

Do you leave the bottom valve open at the start of fermentation? I may have a flawed view of how people use the fermzilla.

Yep. So valve open until dry hop time. Close valve and unscrew the used reservoir. Spray starsan on the exposed area. Screw on the sanitized reservoir with the dry hops. Flush with CO2 using a soda cap connector. Release the valve. There’s videos aplenty on the YouTubeoverse.

 

[Bassman2003]

How about size? Can the Fermzilla fit in your fermentation chamber as easily as a keg?

I went with a used Kegmenter and like it a lot. It barely fits in my wine fridge. I sawed a lot of the round handle material off so the weight is not an issue. ~7.5 gallons is a great size for a fermenter.

 

[madscientist451]

TL;DR: For pressure fermentation, is there any reason other than price to consider a fermzilla over a 10 gallon torpedo keg?



Pros:
+ price (currently ~$90USD vs $220USD)

Use two corny kegs with the dip tubes shortened? Cost would be $50-75?

 

[CyberFox]

I ferment in a 6 gallon Torpedo keg with a FLOTit 2.0 floating dip tube (by far the best floating dip tube). Coming from a carboy, this was a massive upgrade and it's MUCH easier to mitigate oxygen and transfer to a serving keg. I also do a fully closed transfer to the serving keg, which is very easy and makes sure that that no oxygen gets in and no hop aromatics escape.

I was orginally thinking of getting a 10 gallon Torpedo keg to compensate for heavy dry hopping (6.5+ gallon batch size), but the 10 gallon keg wouldn't be able to fit in my freezer. The 6 gallon keg allows me to have 5.5 gallon batches and I don't really lose all that much beer anyway even with heavy dry hops thanks to the FLOTit 2.0 and cold crashing. For the 10 gallon keg, there's also a risk of oxidation due to excess head space if it's not fully sealed for some reason (stuff happens).

Overall, I think a keg is just about the perfect fermentation vessel. It can handle MUCH higher pressure than anything else (including conicals) and it's just built to last. The Torpedo kegs are really nice for the money. I looked at the Clawhammer 6.5 gallon keg, but it's $274 and the 6 gallon Torpedo is only $140. I don't need all the bells and whistles on the Clawhammer keg anyway and I like the regular lid on the Torpedo.

Hope this helps.

 

[mashdar]

Use two corny kegs with the dip tubes shortened? Cost would be $50-75?

Do you have a suggested source? That's about the cost of 1 keg where I've looked, but I may not know where to look.

 

[mashdar]

I ferment in a 6 gallon Torpedo keg with a FLOTit 2.0 floating dip tube (by far the best floating dip tube). Coming from a carboy, this was a massive upgrade and it's MUCH easier to mitigate oxygen and transfer to a serving keg. I also do a fully closed transfer to the serving keg, which is very easy and makes sure that that no oxygen gets in and no hop aromatics escape.

I was orginally thinking of getting a 10 gallon Torpedo keg to compensate for heavy dry hopping (6.5+ gallon batch size), but the 10 gallon keg wouldn't be able to fit in my freezer. The 6 gallon keg allows me to have 5.5 gallon batches and I don't really lose all that much beer anyway even with heavy dry hops thanks to the FLOTit 2.0 and cold crashing. For the 10 gallon keg, there's also a risk of oxidation due to excess head space if it's not fully sealed for some reason (stuff happens).

Overall, I think a keg is just about the perfect fermentation vessel. It can handle MUCH higher pressure than anything else (including conicals) and it's just built to last. The Torpedo kegs are really nice for the money. I looked at the Clawhammer 6.5 gallon keg, but it's $274 and the 6 gallon Torpedo is only $140. I don't need all the bells and whistles on the Clawhammer keg anyway and I like the regular lid on the Torpedo.

Hope this helps.

Do you use fermcap or anything? Any blowoff issues?

 

[CyberFox]

Do you use fermcap or anything? Any blowoff issues?

I use a blow-off tube. More specifically, I use CO2 from fermentation to purge my serving keg (fermentation keg -> serving keg -> jug of sanitizer). The math shows that this purging works even better than filling a keg full of sanitizer and pushing it out with CO2.

 

[mashdar]

I use a blow-off tube. More specifically, I use CO2 from fermentation to purge my serving keg (fermentation keg -> serving keg -> jug of sanitizer). The math shows that this purging works even better than filling a keg full of sanitizer and pushing it out with CO2.

Cool, and spund the serving keg?

edit: er, no spund?

 

[CyberFox]

Cool, and spund the serving keg?

You could do that, but I just run a blow-off tube from the serving keg into a jug of sanitizer. Either way should work.