Aquascaping...or pile of rock

[henryd]

Hello,
I just became the happy owner of a freinds live rock. He is downsizing and sold me cheap 40lbs of rock. In the past I have always tried to arrange the rock in the center of the tank so there was space behind the rock for fish to swim and hide from viewers and allow water flow around the pile of rocks. I have had some issues with rock slides, etc.
When I look at the photo gallery, it seems like most people stack the rock agaisnt the back wall or build from the two back corners with an opening in the center of the tank.
I am planning to start adding xenias and some easy corals - mushrooms, polops, leathers in the next month (Christmas $$).
What do you all recommend? Best way to make sure I get water flow? hide the power heads?
Thanks