which sea salt mix to choose?

[sasha]

Hi There!
I am just starting my first marine aquarium, so far fish only.
Currently I have 30G Hagen tank with 2x20(marine glo+power glo), fluval 204, Red Sea Prizm Deluxe Skimmer ,301 powerhead,heater, hydrometer Carib Sea argonite sand(I am thinking to add some live sand to it to start cycling), bunch of tests, but no water

Well, the first question is there anything crucial that I missed?

And the second one is which brand of seasalt mix is the most reliable?
Thanks in advance