First time brewer query Pressure barrels

[HartleyHare]

I have started my first brew, original Australia lager 40 pint, it has been fermenting over a week, and hydrometer suggests bottling. I wish to transfer to a pressure barrel rather than bottles, and do not know how much sugar required for secondary fermentation / carbonation in a 5 gallon barrel, is brewing sugar required or should i use something else and how much should i use.

 

thanks in advance Sean

[PB2]

G'day Sean, if it's the keg I'm thinking of, there is a discussion thread here