You can have some rocks, but I prefer a egg crate bottom that hold plugs.
Lots of flow
Lots of light, how much depends on what you are growing
Pristine water quality, not just good. Skimmers, filters, anyway you go it needs very low phosphates (for SPS it's < .05)
A shallow tank that is easy to work in is important.
You can have a few fish, like a six line to keep the worms down.
You can start with any size aquarium, 20gallon to 2000gallon.
And patience.