Well with the flame angel, he will nip at your coral. He pretty but a pain. I would go with a tang or butterfly. With the mandarin, if you dose the tank with pods, About once every two weeks depending in your system, he will be just fine. Corals; I started with mushrooms, polyps, and a soft tree. That stuff is all very hardy and will tolerate (no offense) "beginner" water levels. Also once your system is established, I would recommend turning off the uv sterilized to just a couple days a week. It stops your pods from reproducing on their own. It really is a hurry up and wait game when it comes to sw. keep in mind, no two tanks are the same, so make sure you test your own water and learn what you need for your tank.