This is how I cured my live rock and it worked perfectly. I believe that not doing water changes just prolongs the amount of time that it takes to cure the rock.
Place the live rock in a new 30-gallon plastic garbage can. Consider adding bottom drains to the container to speed draining and water changes.
Completely cover the rock with freshly mixed saltwater, with a specific gravity of 1.021 - 1.025
Provide a heater and keep the water temperature near 80 degrees to speed die off.
Create constant water movement with a power head or air stone.
Keep the area dimly lit to prevent algae blooms.
Perform 100% water changes twice weekly.
Scrub the rock with a new nylon bristle brush or toothbrush between water changes to remove any white film or dead material.
Most rock will be fully cured in 1- 3 weeks, at which time it is safe to add to the display aquarium.
When the water conditions stabilize and ammonia and nitrite tests are zero, the rock is ready to be placed into the display aquarium.
