Best way to dose ?

Hey guys are my tank in maturing and more and more coral is being added and growing. My levels seem to drop at a quicker rate ( naturally lol ) so I'm trying to find the best way to keep my calcium, alkalinity,magnesium and ph to where they should be. I'm getting tired of all these supplements I'm constantly adding and my weekly water changes aren't enough to keep my levels high enough. For example in two weeks I went from

Calcium 450 dropped to 400 ppm

Alkalinity 10.8 dropped to 8.8

Magnesium 1450 dropped to 1260ppm

I have a 93 gal mixed reef lps dominant