im going to transfer my cider from FV to barrel today..should i top up the barrel with water or cartoned AJ to make the air gap smaller? or will filling with gas work

thanks
is this cider from apples you have pressed? is so then i would believe you have a lot more fermenting to do, until you are below 1000 SG i wouldn't worry a great deal about ullage.beertrix wrote:good morning
im going to transfer my cider from FV to barrel today..should i top up the barrel with water or cartoned AJ to make the air gap smaller? or will filling with gas work?
thanks