best test kits for Ca and Mg?

[Delphinus]

Originally Posted by Ron99

around 1050 for Mg in a freshly mixed batch of D&D H20cean salt at a SG of 1.025 and temp of about 78. That seems a bit low as I thought this salt should be higher.

Sounds about right. I gave up on the premium salts for this very reason. I got the same reading for D-D myself.

IMO Elos and Salifert are about the best bets for Mg. But as stated already, all test kits generally have their own pitfalls.