What corals do you like? I would start with soft corals and some lps
, but make sure they are corals you really like, because soft corals do tend to grow fast, and some times take over.
Just don't make the mistake that many of us do in the beginning and put anything in the tank just to have something to look at. No brown corals!
You'll need calcium, alk
, and mag test kits eventually..once you fill your tank up.
I assume for now you'll just be doing weekly water changes to replace trace elements?