Do you have sand in there?
Are you adding live rock or base rock?
The answer depends on the answers to these questions. But assuming a standard reef setup with live sand, live rock and protein skimmer, then there is no cycle.
If you add established live rock with good corraline algae coating, and lots of pods and worms inside, and have live sand that again has a good mix of pods and worms, you may not notice a discernible spike in ammonia or nitrite.
If adding base rock and only one or two cured rocks, then you may notice a cycle but the algae and pods will quickly reproduce and spread. Same for adding a bit of live sand to sand-from-a-bag.
If you go to ebay and search on "detritivore" you can get a kit from which will really kickstart your rock and sand. I highly recommend his kits. My tank bounced back from a disaster within 2 weeks and is back to stable. He'll send lots of pods, worms, brittle stars, several pounds of virtually bubbling live sand, and macro algae for your fuge if you have one.