Alk calcium magnesium phosphate levels in reef tank

Hi I just recently got a dosing system it's an eshopps two parts for now just dosing calcium and alkalinity and hand dosing nopax i am starting out with small amounts of additives and move up slowly until I find my sweet spot for levels I was wondering what would be considered dosing a low amount in ml to start out and also I know calcium should be around 450 ppm and what should alk be I've read either 10 to 12 or 8 to 9 thanks