Yes, I see what you meanI'm just using a standard JG fitting, they are much better than barbed fittings particularly if your hose is a loose fit, small hose clips often dont work that well.
I connected it to the regulator's brass connector with a hose clip and CO2 escaped at that very point. I'll have a look at the JG site to see if they do a fitting with 1/8" thread, they don't seem to list the size of the 'other' side i.e. where the hose pushes in.edit:oops, yes they do...