I have a 29 gallon tank with live rock and live sand. Protein Skimmer and circulation pump. I have recently added 1 turbo shrimp, 2 narcicuss snails, 1 peppermint shrimp, 3 scarlet hermit crabs and 1 astral snail. I would like to have coral, invertebrates and fish. What should I add next - the coral, invertebrates or fish? Thanks