@EMeyer
ever hear of garf.... Your "live rock " is no longer available in the trade. Funny my petco live sand package disagrees with you... My 4 inch concrete root cellar roof drips water when it rains i.e. porous. My cast off concrete I'm using has the same structure as anything from back in the day, yes holes measured in inches. My bio diversity comes from ruble and frag plugs including algae for my ATS, fan worms, pods, coraline algae after four months. I can add worms, sponges, and other cryptic fauna (Steve Tyree) waiting for the system to mature a little longer.