I was wondering, what would be a good coral to start out with? My tank is 20 gallons and has been up for about a month and a half and I currently have 1 Scooter Dragonette, 2 Firefish, 2 Emerald Crabs, 1 Coral Banded Shrimp, and 4 Dwarf Blue-Leg Hermits living in it. I want to add something to give it some color in about 4 or 5 months and I would like to know what is relatively easy to keep? I like star polyps but I wasn't sure if they are easy to keep. Everything I have read says they are but I wanted someone else's opinion too. Thanks!