You should keep that clown fish in your tank for at least 1 or 2 more weeks before adding new fishes. Also, the safe way is only add 1 fish per week so you don't have to deal with mini cycle. You must have a quarantine tank, soon or later you will waste all your money because of diseases killing all your fishes, medication usually NOT an option in a main tank. You will need more rocks if you want more fishes, create more caves, hangover. You can visit some LFS focus on saltwater and look at their display tank, you can see 3/4 of their tank volume are fill with live rocks and fishes are happy with those setup.
Note:
It's not recommended to buy baby fishes, they are hard to keep in newly tank setup.