So which Mg test kit is right?

[dough]

I can a Salifert (Exp 09/2011), Salifert (Exp 11/2009) and Elos (1 year old) Mg test kit side by side at lunch. The results where:

Salifert (Exp 09/2011): 1275
Salifert (Exp 11/2009): 1320
Elso: 1800

I was surprised by the huge spread. Even ran the Elso twice.

So which test kit is correct?

 

[dannybradley]

I've always been happy with Seachem Magnesium and Borate Alkalinity for testing Mg.

What do you dose to raise your magnesium?

 

[dough]

I'm using Bulk Reef Supply Mg chloride and Mg sulfate in a 2 part blend.

 

[dannybradley]

I don't think it's true, but I was wondering if the Salifert kits are sensitive to only one form of magnesium. Backing up that I'm probably wrong, is that their Mg supplement is a blend of several Mg compounds.