Are you keeping any zooxanthellate corals, like softies or 'shrooms? They would perhaps do better with a "blue-er" Kelvin temp lighting like 10,000 K with actinic .03. There is some limiting factor involved here, and it is hard to grope for it in cyberspace without good photos and a more comprehensive log of your aquarium with more water test params shown and a list of all animals and how long this tank has been set up. It may just be too new and unstable an environment for a fuge to work in yet - they do take patience and a more mature set up to work their best...a decent animal load (healthy not hasty!) help to feed macros, otherwise one would have to supplement, but that is no area for a beginner to enter, believe me! As long as your macro is not dying, just a little patience and small regular water changes to renew trace elements are required at this early stage.
Your dinoflagellate bloom (green water) is probably light cycle, nutrient spike and low K temp related. Magnesium and iron are more important to most macroalgaes of the "fleshy" (Chaeto, Caulerpa, many others) VS "calcerous" (Halimeda, etc.) and "stony" (coral-shaped hard, and scale) types than calcium and even iodine (those traces are more intended/aimed at corals than the fleshy/soft macros in general).
