Fermenting 6 gallons in a 14 gallon fermenter? Problems?

I am thinking of picking up one of those 14 gallon fermenators because I want to make some 10 gallon batches, but occasionally want to still make some smaller 5 gallon batches. Is it okay to ferment a smaller batch in one of those - or would all the extra headspace be a problem?

Thanks.

Can't imagine any problem, any air should be displaced by CO2 from fermentation within a day or so, which will leave an inert layer over the beer regardeless of the headspace.

Of course you could boil some bricks and put them in first to reduce the available volume, we used to do that to save water in the comode.

The o2 in the headspace will be used by the yeast in their aerobic stage and the co2 released during their anearobic stage will push out and leftover o2. So.. you'll be fine.

No worries. It is done all the time.

Are we talking about a 14 gallon conical? Lucky! I'm just jealous as my converted keg fermenter is good but just doesn't have the flexibility of the conical. Enjoy.

Yeah the 14 gallon conical. I want to try harvesting yeast and using it in subsequent batches and... really all that stainless is just sexy. I'm still on the fence about it though.

The boss at work screwed up and demanded we start being there at 6:30 when the doors open "in case something breaks" (we're in I.T.) so I'm working 10 hour days. It sucks, but the overtime is great for buying toys.

I've thought of converting a keg for a fermenter as it would save loads of cash. How is yours working?

Mine works great for fermenting but for yeast harvesting that's a different story. I've seen some modifications that others have done that seem to allow them to remove some of the trub and yeast but according to them their designs still don't work as well as a conical but I can ferment for 7-10 days, add gelatin and wait a day crash cool, then rotate the racking arm and remove very clear beer. A little more work than those nice conicals but works nice enough.
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