and if you do not have the rock on egg crates how do you keep the tank free of fish waste? How do you keep dead spots clean or keep it clean under and around the rock without moving or disturbing the live rock and or corals etc.
I've used eggcrates before to keep rocks stable and off the floor, but my most recent tank just has the rocks sitting on the sandbed. I prevent dead spots the best I can by making sure I have a lot of random flow around the tank. The rest is taken care of by mother nature (that is, natural processes in the tank). It has never been a problem for 10 years.