How much live rock

[mattduv]

I will soon be getting a 30g tank and want to use live rock and sand. How much of each should I get and how much live rock is needed to act as a natural filter so I don't need to but one?
thanks

[Marcotte]

Just a newb myself but I believe the general rule of thumb is 1.5 to 2 lbs of live rock per gallon.

[Reefscape]

About 1 - 2lbs per gallon of tank water...this is about the same for rock and sand...