How do you know when LiveRock is done "Cooking"?

[Myka]

Click the link in my signature for more info, but the jist of it is to put the live rock in a bin/tub with no light, just heater and powerhead for several weeks doing weekly 100% waterchanges (for fastest progress) until both phosphate and nitrate are undetectable. It is essentially taking "curing/cycling" one step further and flushing the nutrients out of the rock. It helps to prevent algae issues from the rock leeching nutrients.