[Myka]

SG of 1.030 won't cause any significant die-off...if any at all.

Cooking live rocks is when you place them into a dark container with normal salinity saltwater, a heater at normal temp, and a good powerhead for circulation. You do weekly 100% waterchanges, and swish the rocks around during the waterchange to remove all the detritus as it falls off. You keep doing this until you get a Phosphate reading of 0.

This is usually done with rock that is suspected to be leaching phosphates into the water. Tanks that are having severe algae issues are prime suspects. I also do this with any new LR - cured or uncured. I figure what's the point of introducing phosphates to the tank when you can get rid of them in the first place?