Half Full Fermenter / Brew Size

[OldEvan]

Hi Everyone,
I have a coopers 30L fermenter, and coopers tins make roughly 23L of beer. Recently I noticed that Malt Shovel brew cans only make about 15L of beer, and coopers ginger beer only makes 20L.

Can I just use my 30L fermenter to make a smaller batch? Surely the CO2 produced in fermentation would cover the wort anyway and prevent the half full fermenter being a problem? Alternatively I guess I could make a double batch, but that would be a bit risky topping the fermenter right up (and not to mention, a double coopers ginger beer wont even fit!)

Thanks for the help

[stevem]

I recently made 2 half batches (12 litres) in a standard size fermenter. Did not have any problems.

[Lebowski]

I normaly make my beers only up to 20 or 21 litres to save wastage when I put it in the keg, havent had any problems. If I was doing a malt shovel I'd probably just buy 2 cans though.