Magnesium?

[Wretch]

I have had my tank up and running for about 10 months now. I have 5 fish and some corals(zoas and lps). My magnesium has always been low, somewhere between 1100 and 1000 but last I checked it was at 960 or so. Would this low magnesium be preventing my coral from growing? Almost all my corals are the same size as when I got them. My other numbers all seems normal.

Salt 1.025
Calcium 420
KH 8.6
Mag 960(have been raising with tech-m now at about 1200)
Temp 79.2
Using a D120 LED light

Any thoughts on this?

Thanks.