If its not cured completely then the die off on the rock will cause an ammonia spike. Only way to do it would be 1. to buy base/dry rock, which is my recommendation since it cheaper and safer and will become live quickly, 2. Buy live rock and put it in a container of saltwater with a powerhead and let it cure over the course of a month, takes too long for me. 3. Buy 100% cured live rock, this rock is much more expensive than dry rock or live uncured rock and its too much in my opinion for something that cheaper rock with turn into very shortly. In 2-3 months my base rock was almost completely covered in Coraline algae with a nice purple color.