Not sure, but theoretically you could measure your gravity and not have to add ANYTHING. Just bottle when the residual sugars are just enough to achieve proper carbonation. It's a risky venture, though. I'm sure someone much smarter than I could chime in on the wort addition for priming, or you could figure it out with the right combination of brewing calculators. Actually, I think I saw a table in a book on the different methods and amounts for priming. Hold on.