I use alot of Alkalinity buffer, Seachem Reef Builder, about 2 tsp every 2 days in my 55 gal.
Also 1 tsp of Kalkwasser in a gallon of top off about every third day.
Very rarely a bit of Calcium buffer if things are getting a bit on the low side.
Also, about 15 gal. Weekly to every other week water changes to which I add 2 tsp of Alk buffer to get it up to display tank range.
It really does depend on the tank though. But Alk. is the biggie in my opinion.