What kind of tank are you going to be using? Or, is that a secret?
Depending on what salt you're using, you won't need to supplement calcium with the big water changes you're planning. When I was doing 10% three times a week on my first reef (a 10 gallon) my calcium was really high as I was adding it faster then it was being used. I was using Reef Crystals, and that mixes up high in calcium at 1.025. I had to cut back my WCs to bring my calcium back in line.