I have bought about 80 lbs. from Tampa Bay SW
- they are small - brick sized rocks with enormous amount of life forms in/on it, my last shipment was plucked from the ocean that morning- packed in water, so shipping is more and I had to pick up at the air cargo area of Midway airport.
I have also purchased about 150 lbs. of Marshall Island rock from Premium Aquatics. I asked for and got very large pieces ( all 15 - 30 lbs. each)- it is a nice open/ porous rock, but not so much life - packed in wet newspaper.