I just got my first, plating coral, i also have clams and my tank is heavily stocked with corals,that is why i wanted some infro on itI auto two part dose and use kalkwasser which is inline with my ATO. When I was reading about it a few years ago I thought it also aided in Phos reduction as well. (I use rowaphos ) I have some larger plating corals and some SPS in a 4' tank and do have trouble keeping up with Alk and Ca so I assume the Kalk just helps top off my 2 part. I've tried lots of stuff over the last few years however the inline Kalk (although I have no real correlations to parameters) is something I will continue with.