I'm not going to that extreme!! Almost all of my live rock in both reef tanks was "used" before I got it. The only problems I've had is a single Aiptasia that I haven't been able to kill off. It hasn't multiplied and has hardly grown. I give it a kalk meal about once every 2 months which seemingly kills it but it must not because after about 6 weeks, I notice it again. Always in the same spot. The beginning live rock that I did buy from a LFS came with several Aiptasia but they all succumbed to the first dose of Kalk paste. Any algae problems I've had with my tank were fixed when I got my RO/DI unit so I can't attribute those to the used live rock either. I appreciate everyone's input but think I'll just QT it for awhile longer and then watch it closely in the tank. May even QT it in another glass tank so I can see it better than I can in the plastic garbage can...lol. I do think I'm going to stop taking it out and sniffing it though. Neighbors probably think I'm NUTS. Wait, I am sniffing rocks....I AM NUTS!!! lol