I'm in the process of getting the 58 up and running. And I've come to the point where I'm pondering a sand bottom or bb. I'll be running a sump and thought I might put sand in it. I've got two bags of sand that I scored from the guy from colorado that was making a trip back from the east coast. My reef will have zoo's, rhodactis, ricordia, a few leathers and SPS. I'm also considering a goby/shrimp pair, but it's not high on my priority list. I really don't want to deal with a sand storm and a nutrient sink. If I go bb the goal would be to try to get zoos to cover the bottom, it might be kind of cool.