>Karen wrote: >I have never seen a testkit specifically for calcium. Who makes them? La Motte, Hach and Merck too. At least here in Europe, I don't know about North America but surely you can have more chances to find out as the 1st two are US companies. Anyway, as I said before, a magnesium test (direct or indirect) is not the _right way_ of looking for a magnesium _deficiency_ . Ciao!:) Luca