I know a lot of people use the one Domino sugar cube per 12 oz bottle for priming. The sugar cube is 1/2 tsp, or about 2.3 g. So, I am not sure how @odie isn't over-carbing by quite a bit with 1 tsp, 4.2 g. Unless his sugar is particularly large-grained, which would make for a less dense tsp.