Marco rock is dry rock. You can save a ton of money by using mostly dry rock with some live to kick off the cycle. My LFS suggests 1 lb of live for every 10 lbs of dry. I did this and it worked pretty well
agree with northstar. i used the same ratio in my tank when started it and it worked great. the rock form macro rocks was great and easy to work with. if you tank is smaller i would use a little more live rock just to get things moving faster.