The Rock got from BRS was 'dead coral' its not just rock - similar to this from Marine Depot. https://www.marinedepot.com/AquaMaxx_Tonga_Shelf_w_Base_Dry_Live_Rock_20_+_Inches_25_lbs_Dry_Rock_for_Saltwater_Reef_Aquariums-AquaMaxx-UJ2725-FISSLR-vi.html?utm_source=mdcsegooglebase2&utm_medium=cse&utm_campaign=mdcsegooglebase2&utm_content=UJ2725&gclid=EAIaIQobChMIgd2LoJr93wIVUNbACh09nQU-EAQYAyABEgKE2PD_BwEI have one tank w/ dead rock from BRS b/c I wanted to be enviromentally friendly. Earlier in my hobby I had live rock flown in for another tank. I personally think the live rock is 100% better and ended up swapping between the 2 tanks to add depth to the dead rock system. I found the DR to be very light? Have you worked with both? Ever notice any differences?