If your dKH is 9 - 10 and you can keep it there, and your calcium is 350 - 450ppm, and you're not getting good growth, then adding more Calcium will not help. You need to look elsewhere. Are the coral feeding? Is the water temperature appropriate for the species? Is the PH appropriate? Is Phosphate low? Are they getting enough waterflow? Is the light intense enough?
Possibly im too impatient and i expect more from my sps and lps corals than they can do? I mean my green monti cap has been in the tank for about 2 months and it has visible growth and has attatched itself and my pavona has been in the tank about 5 months and it has definately attatched. But my frogspawn (or at least thats what i think they are, one was sold to me as a non branching frog spawn and one as a hammer, but some friends say neither are frogspawns and the one sold to me as a hammer has pink dots instead of scythe shaped tips)... anyway, my frogspawns dont really grow. Ive had my non branching like 8 months but its only grown one full sized head and like 10 baby heads that dont get any bigger. My other frogspawn, which i think is a branching frogspawn, i bought it as an experiment about 5 months ago. It was clearly dying, it had 7 heads and 5 died off, leaving me with 2 heads, now its upto 5.
Am i expecting too much out of them? I mean i only spot feed on occasion cause i think its annoying, but i know they catch frozen meaty foods when i feed the tank because i watch them do it. I keep my tank at about 80 deg. I believe flow is good, i have plenty but its not beating on them and i have led lights, which i did see some growth after getting rid of my mh and switching to led (more light and more intense too). Not sure about phosphate, i dont have a test for it. Ph is 8.4
If phosphate is the problem, how do i fix it? What other test levels could be affected if i fiddle with adjusting it? Why and how does phosphate drop? I really have no knowledge about phosphate. I will buy a test and see if thats my problem, and i will buck up and spot feed more often lol