180 lbs sounds good to me. you could honestly get away with only 30 lbs of LR and the rest base rock. your reef tank is going to take a while to mature anyways, so in this time most of the rock will be partially live. I consider a reef tank never being cycled, its about controling the cycles. Your always adding things, and chemicals are always being released into the water, so there are flucuations that occur during lights out. a good sump system and skimmer is your best friend. id recommend at least a month for your tank to cycle. even thought live rock is typically enough to start the cycle i always recommend doing the shrimp deal as well just for extra messure.