janey you have alot in there, lets see pic when you move things.
I just added a Coral Beauty to my 15g , a really pretty fish. I will not be able to keep him in there very long he is 2" now, I will move him to my 75g when he grows some. But he really brings my nano to life. I also added two cleaner shimp. The tank is doing very good , the only maintneace I do is 2.5g water change/week, and top off dailey with ro/di water.
I need a couple more corals, but I am keeping the corals very simple in here, I have to trim back the Xenia very frequently.