When I run out of reagent I may switch to salifert for magnesium. I don't really like the magnesium red sea test.Just a PITA for me. Not sure why it needed extra steps.
I get a good consistent answer in less than 2 minutes with Salifert. I use the other Hanna’s and they are great, fast and easy. Salifert MG test is just as fast and easy.