Curing LR is a process not a type of rock it involves scrubbing the dead/dying crap from the LR and separating it from an aquarium environment for a period of time in order to kill off any unwanted hitchhikers, algae's, or unwanted bacteria's.
The reference term used to describe ready to use LR is aqua cultured - this stuff is pre-cured , cycled , and contains colonies of both aerobic and anaerobic bacteria's. With proper levels of both Alk and Lux coralline algae happens.
Lighting is not the only issue with reefs infact it may be the easiest aspect of reefing. Nitrates + Phosphate management come into play making bio balls a double negative - they expel Nitrate + Po4 by design in, a reef this is not were you want this process to occur. Fish can handle PO4 + Nitrates up to 20 ppm a reef not at all think less than 1ppm of po4 and nitrates steady at 5 ppm. Alk also comes into play as lower levels of dissolved sodium are more fish friendly however stoney corals use alk elements to grow. managing stable higher levels of alk brings Calcium/sodium creep into play - this stuff will chew up and clog HOB's rather quickly. Water circulation is also an issue as corals need a fair amount of current just to shed their mucus membranes.
A protein skimmer is extremely advisable with reefs as it helps rid the water of dissolved waste. This TDS leads to higher levels of nitrate + Po4. As for carbon - it's an on the fence thing, has it goods and bads - one benefit of carbon is that it does very much help remove toxins from the aquarium generated inside the tank it's self, toxins produced from fish, corals, and decomp.
It will remove trace stuff like heavy metals IE iodine or strontium if used on a full time basis however reef carbons has instructions - use only 48 hrs a week discard after 30 days.
