First off, I would do some research on this subject, read some books.
Cycling a tank is the establishing of bacteria in the tank that break down toxic ammonium in fish waste into nitrites, then nitrates. People usually don't cycle with damels actually, because it subjects the damsels to stress from the ammonia and nitrite. What you really want to do it a fishless cycle. Put your live rock in your tank (if you have any), then put a raw table shrimp in your tank. Measure the levels of Ammonia,Nitrite, and Nitrate until the Ammonia is at 0, and the nitrites are at 0. The nitrates will probably be between 0-10 ppm. do a partial water change, then wait until the Ammonia is at 0, and the nitrites are at 0. Do another water change and your done! Then you can start to add your CUC. I would wait about 1 week of monitoring before you add any fish. If I were you I wouldn't waste your money on "bacteria in a bottle" because all of the bacteria is in the live rock. If you have questions just reply
-mohawkninja