Hard to say how ong its going to take to cycle, but I would definately go the dead raw shrimp approach and leave the damsels or any other living breathing critter out until its cycled. I have mixed thoughts as to what everyone says in "go bigger".WHY? I have laarge tanks, but my preference is smaller setup, 20 gal and smaller, mainly 5 gal or smaller is my favorites...If I did not have so much money invested n my larger setups I would take them down and make room for more small tanks....A lot of people think SW is neat, and go nuts on buying large setups, and then find out its not really something they want to be tied down with....then again some say larger is easier to take care of....I do not buy this as I started with a < 2 gal pico as my first setup and its not been a problem of any kind, and a properly setup and maintained smaller tank can be just as diverse and much cheaper to keep than a larger tank.
If your intent is to add more LR later, its going to extend the cycle yet longer, so why not add what rock your intending to add from the start and let it cycle and be done with it.
Just keep checking your ammonia levels and nitrite levels. When they hit zero, your tank is cycled.
I like to use those devices called ammonia alerts, when I setup a new tank. They change colors at different levels of ammonia. INitially they indicate yellow and safe and within no time at all yu can see the indicator dot change colors........SInce there is not much you can do to a tank in the cycling stage, but wait and watch, your not apt to mess anything up and it elimiates the urge to do ammonia checks. When I see the indicator show my level of ammonia is safe again, I then do a water test......
You can get these little ammonia alert devices in most any LFS for under $5. once tank is cycled and runnig correctly I still leave them in the tank, as a quick visual indicator. I still do water tests, and use the indicator as a quick visual.
