what should Itest for in a fowlr tank
Setting Up a FOWLR AquariumYou need test kits for: ammonia, nitrite, nitrate, calcium, magnesium, alkalinity, and pH as a minimum. If you choose to use a pH meter, you don't need this kit.
Found this on a Site for you about setting up a FOWLR System...hope they help..as it's an old Forum..but looks like you Test the exact same things as you would any other Marine Aquarium..
Setting Up a FOWLR Aquarium
http://www.aquabuys.com/c/fish-only-live-rock-aquarium.html
Fish-Only, FOWLR, or Reef: Which Aquarium Setup is Right For You?