What rock should I use?

[Snappy]

I also suggest using all live rock. There are lots of good shapes and sizes, also many varieties. I recommend mixing it up as each type has it's own merits.
In my tank I have a mix of approx 350-400 lbs of live rock from Indo, Fiji, Caribbean and Tonga so together it makes a good mix. Live rock is something you can always add as you need it. My reef tank is almost always under some sort of construction.
Good Luck,