I read all of the posts and honestly my mind just circles back to one thing, why not just do a water change. If your trates are high, its obviously been a while since your last one (or over stocking over feeding) but your already down on certain elements, your gonna have to do a water change to replace them (you cant supplement for everything) why add stuff that can possibly present future problems. I myself am going to avoid dosing with sugar untill there is a sugar test kit for marine aquaria.... LOL ok the last was a joke.
I'm not critisizing any one who prefers those methods, I am just leery of adding anything I dont have a test kit for in my mad scientist lab.