Hey guys, I'm starting up a 55 gallon saltwater tank. Right now, I'm running a fluval 304 filter(carbon/nitrate sponge/bio rings) and berlin air-lift 60 for my filtration. My substrate right now is 80 pounds of live sand, but I want to add about 60 pounds of live rock. At my LFS it will cost around $450. I don't have that kind of money right now, so I've been looking for alternatives. Found a few websites that offer ways to make your own live rock using Portland Cement and Aragonite sand. My question is, is this really something that's safe to do? I'd love to do it, but I know you can't believe everything you hear on the internet. Also, is it something I could do without having any "real" live rock, or would I need some real live rock to seed it? Thanks a lot!