JenCliBee
PleC & CorY MaD
Just so that you know it is done both ways, most of the LFS I know of just tie the bag with 'air' in them, but one place I go to specialise in Koi and goldfish, and those fish are always placed into bags, with probably 50% water, and then pure O2 put in the other half of the bag. I guess they use O2 because of the reduced 'air' volume in the bag, because of the amount of water they put in for the fish. (whether this was to dilute waste etc during travel I don't know, it's just what they did).
On that note actually, it seems people also advise starving your fish for 1 or 2 days before they travel to minimise the waste they produce whilst in transit
i think they do it with koi and goldfish becasue they usually require much bigger bags and if u havent tried trying 2 fill x-large bags with air is a pain in the rear end lol
but it may well be for different reasons lol 
