well, i've been using the marina led light for a month and a half now, honestly, it was working just ok, i had some growth, but not much. My chaeto use to be right next to the light at the top of the water, but then sunk to the bottom and then became mush. Either because it was not getting enough light or something else.
Either case, I did some more research and I'm going to try plan B and get the submersible 10w lights found on discount pumps dot com and see how that works. If that doesnt work, i may have to try scraping off the back paint of the nano and adding an outside PC light fuge to it. We'll see