Too much headspace in Fermzilla?

[Brian66]

I recently got a good deal on a couple of used Fermzilla fermenters - I believe they are all rounders and somewhere around 7 gallons. However I brew small batches of 2.5 gallons.

Will it be too much headspace if I ferment 2.5 - 3 gallons in the Fermzilla?

I've been working on hazy IPAs and something I'd really like to try is to ferment in one fermzilla and use the second fermzilla as a secondary for dry hopping - the purpose being to be able to stir/agitate the hops in the secondary.

Would there be too much headspace in the primary and/or in the secondary? Also - what are some good practices for stirring up the hops if I try this?

 

[Broken Crow]

IMHO you'd be fine for primary, but unless you want to do a whole 'fill completely with star san and then purge with a lot of CO2' to the second fermzilla, I'd go with a smaller secondary as close as possible to the actual batch size. There is no shortage of complaints on here, even with O2-free methods, of 'loss of hop-aroma' which after eliminating the impossible, inform us that at least some portion of that aroma is lost to the headspace...even when it's near-pure CO2.
If you're still looking at buying more gear if needed do do this, you may want to consider the 3G fermonster with the CO2/floating diptube mod: https://www.homebrewtalk.com/thread...lete-closed-transfer-system-for-cheap.680992/
Even just going down to a spare 5G corny for secondary would probably be a better route.
Again; Just my opinion.

 

[Brian66]

Thanks! Was thinking if the fermzilla for a secondary was too big I'd secondary in a 2.5g Keg and then could transfer to another Keg - using a floating dip tub.

 

[Broken Crow]

Thanks! Was thinking if the fermzilla for a secondary was too big I'd secondary in a 2.5g Keg and then could transfer to another Keg - using a floating dip tub.

Again IMHO; Excellent call! I do though, hope you have more than one 2.5G keg..for something with a lot of hop-aroma, you'll also want to minimize headspace in the final serving keg.