Rich, have you ever considered vokda or carbon dosing, even the simple for of it and goign with biopellets in a proper controllable biopellet reactor?
i'm not a big fan of the lights out thing, you're going to end up killing off the algae which with basically cause more nuitrients to appear, causing the problem to come back.
the source is excess nuitients so you have to do what you can to limit it and just keep up with your water change. make a wetter skimmate to force more out just be sure to monitor your salinity because i'll force out more water and you might top it off with more fresh water then needed