New reef tank! 41 Gallon Fluval Osaka. Suggestions?

[Aquattro]

As I mentioned elsewhere, ditch the internal filter and the lava rock. You have no idea what's in it, and you don't want to spend thousands on corals and have to ask one day why they keep dying. Lava rock is an unknown and should not be in a tank. Save yourself a lot of potential grief right up front and go buy 15 pounds of fresh live rock at the LFS. Make sure it's new rock, not something they bought off someone else shutting down. IMO the biggest mistake in this hobby is using somebody else's old rock.
Other than that, the list looks fine. Brown stuff is diatoms, perfectly normal and will go away on it's own.