Here's the tank pre setup.
Mine says 4-4500k on it. it was sold as white, but for a 30W with a plug it was the only option, it's actually not very yellow. I'd try to get one sold as "cool white" should be close to 6500k. The shroud, was taking some "great value" aluminum foil, folding it over ~3 times-in the desired width, trimming it to the right length, then scotch taping it to the fixture. It doesn't get very hot so it should be fine for now. IF you rest it right on the tank, the spread won't be an issue though. I plan to have an emersed grow box behind the tank(the black thing), plus it's just one light and a 30" tank-that is why I hung it up high.