I'm not the one to help determine if that quarry rock is good for a SW
tank or not. Maybe the PH readings might tell you something. Dunno.
At first look, the rock could be a lot more porous than that quarry rock. Nooks and crannies is what you want in live rock. Large surface area that isn't necessarily heavy works best. Those nooks and crannies harbor beneficial life in a SW
tank. Look up base rock. Cheaper, has nooks and crannies, and will become live rock in little time if added to the current setup - and maybe with a plan to replace the existing rock over time.
Check out (Hang on back) protein skimmers and read up on powerheads for water movement. Also, read up on T-5 lighting. I hear good things about it.