co2 tanks...

Sorry mate, just got out of hospital!. I use the small 2.6kg Keg King ones, The larger one of 6kg would of been better, but the 2.6kg lasts around 8-10 kegs at least with force carbing. I find the keg king ones a good deal as they are the only real swap and go CO2 tanks I can get around here cheaply, swap and go also means lifetime warranty etc. Another option is to rent a big bottle from one of the suppliers but rent yearly isn't much cheaper than buying a tank out right. I think you need to weigh up what suppliers you have near you so it won't be hard to refill or swap, some shops are very picky and will only fill certain brand tanks etc. Also ask you local Home Brew store what other locals do. Cheers!