I get this question quite often so thought I would post it here. These are my tank parameters that I shoot for. Sometimes things do swing outside of this range but for the most part they are pretty stable.
Temperature: 76 - 76.5 F
Specific gravity: 1.025
Calcium: 400 – 450 ppm
Alkalinity: 9 – 10 dKH
Magnesium: 1300 – 1350 ppm
Phosphates: .02 – .09 ppm
Nitrate: 5-20
Lighting 120w leds and high flow for all coral.