Who needs condoms? I go 100% live rock, and have none of the problems people have when they use dry rock. I see so many threads about high nitrate from people using dry rock. And insanely long cycles. Those dreaded hitchhikers are going to find a way in your tank unless you're never going to have anything but a tank of rock. Once you put some corals in there, they will be introduced. There's the occasional bad hitchhiker, like mantis and whatnot. But what about the millions of good ones? I have a breeding population of chitons, snails, starfish etc. that are hitchhikers. They're an essential part of my clean up crew by now. I'm not saying that its impossible to be successful with 100% dry rock. It happens all the time. I just don't have the patience to wait a month for a cycle, and add one frag every couple weeks. My tank fully cycled in 7 days with tukani rock, I put a clownfish in it that day. (still in there today too) I started adding corals on day 10 (also still in there)