When I first saw this I thought it was a 125 gallon long lol. But if its 30gal then here's a decent list:
Need:
30-40lbs of Live Rock
Powerhead of some sort.
The filters you have are fine.
Heater
Accessories
T5 Light (for corals if you want to expand later on)
Skimmer (it will help)
For stock, clown fish are a good choice for centerpiece fish(
Occelaris Clownfish). I would suggest some kind of small
goby or perhaps a dartfish(
Firefish) as a tankmate. For inverts, I would suggest either Peppermint Shrimp OR Banded Coral Shrimp - not both, as I hear saltwater shrimp will kill each other. A few tiny hermits(Dwarf Blue Leg Hermit) and some Cerith Snails would be good for a FOWLR tank.
Here is a full list of cleaner inverts.
You will want to give the tank a LOT of time to cycle, at least 2 weeks, more on 4, before you add any living creatures besides the live rock. Fish shouldn't be in the tank until at least 6 weeks in I would think, and you should start with the firefish/goby, as clowns are territorial and will claim the whole tank if put in first.
If you ever want to do corals (which you probably will lol) you will need a T5 Light of some sort, and do not skimp out of such things.
On that note, don't skimp out on anything for a salt tank, it WILL bite you in the rear later on.
Welcome to the salty side, and good luck!