About half of the live rock in what will become an octopus tank is what one might refer to as deco live rock. It consists mostly of the skeletons of dead acropora. There are parts on some of them that are smooth, but I am worried that they are not ideal for an octopus. They might even be a danger. A picture of the live rock is attached. Is this a legitimate concern? I've noticed that no members of tonmo have rock like this in their tanks.