I use Salifert for about everything now except for nitrate, phosphate and alkalinity. Mg isnt a huge deal. If LFS says "it's normal" dont sweat it. It doesnt get depleted near as fast as the other elements. It acts as a buffer between Ca and Alk amd keeps them from binding together before corals can use them.
Glad the birds nest is opening up. It's a tough one.
Glad the birds nest is opening up. It's a tough one.