I added Reef iodide, Reef carbonate, Reef trace, and Reef complete(all seachem products) to my water and the mushroom and the zoanthids look a lot better.
The tank looks great. You will probably want more live rock to colonize more of the necessary bacteria for keeping the water clean. Keeping the fish load small will help when you have such a small amount of live rock.
Rick
I have a Penguin bio-wheel 200 power filter, so the bio-wheel has a lot of bacteria on it.