I'll have to agree with Aaron. You will want to put your powerhead in a place that gets you the most current in your tank. I don't know your setup. But I would suggest multiple PH's. You might want to have one just for the area behind your LR
A great idea a friend of my had was to take a PH, point it down. Run a piece of PVC
to the bottom of the tank, elbow and attach another PVC
along the length of your tank. Cap the end and drill small hols along the Horizontal PVC
. This will use one PH to distribute current throughout your LR
I've got a bit too much LR
to do that now but if I ever move my tank or get a larger one, I'll be fitting it with this setup.