There's a fair bit of trial and error at first until you find the right amounts. Right now there isn't a lot of draw in your system so start off small. Basically I take an amount, and dose it everyday. Then I test. If things are too high, I use a smaller amount and try again for a week; if things are too low, then I increase the amount. If I'm really not sure of the rates I might test everyday at first until I'm comfortable I'm not pushing huge swings on the tank. It's better to let things get little depleted than it is to push a wild swing on a tank.
At this point it's no big deal mind you, but as stated already, alk is one you don't want to adjust too much in one go. Particularly SPS are sensitive to this, you get "alkalinity burn". Make small adjustments and it should be OK.
Hope this helps..