This used to be easy when most pubs had the smaller gas bottles, I used to get one and a replacement when ever, however most pubs here are now on the large bottles, the only way round this was to set up an acount with air products or other such (bring a big wallet) and get food grade mixed gas, now it lasted ages but the rental was mad. Now days I use a local CO2 filler, he does coke, fire extinguishers, dry ice for medical, he gave me 2 bottles and fills them for about 11 euro each, I also bring him some beer. so no more mixed gas for me unless I want to rent a bottle again, my company already has 6 big bottle rentals for welding etc but mixed gas in not worth the expense or trouble for me.
The only way for you that I can see is to find a pub with the smaller bottles and ask, in Ireland there would generally be no problem if you were local, not sure of what it's like where you are. The way I use is just be nice and offer them somthing, besides cash, as it's too blunt, barter with somthing, I duno, it's up to yourself really.
Bru
adm just posted before me and I think there is your answer
