I am really curious about hitchhikers being such a concern with the use of live rock since I've never dealt with any hitchhikers apart from bristle worms, some crabs, and maybe a few other very minor hitchhikers that aren't very memorable at the moment...I've always used live rock that's come straight out of the ocean which seems like it would carry a pretty high risk or highest risk tbh concerning hitchhikers. However like I said that hasn't been my experience although I see others posting about all their hitchhikers on live rock. Where is your live rock coming from? In other words is it possible it's been sitting together with a ton of other rock and maybe only one out of a hundred pieces had hitchhikers but they spread throughout the vat and infected other pieces? That seems more likely tbh and I next time instead of avoiding live rock, why not just ask some preliminary questions given the numerous benefits to use of live rock. I really am just curious. It seems like logistics in getting the rock to your tank plays a significant role in your hitchikers both in number and in what they are.