I'm relatively new to kegging. It seems such an obvious question to me but I've not seen this addressed anywhere so I figured I'd ask. In bottling you add sugar to each bottle to eventually carbonate the beer. With kegging, the carbonation is accomplished via CO2 from the tank. So do you add sugar when kegging, or not? If so, when? If not, doesn't that detract from the flavor and chemical composition of the beer? Thanks in advance!