i have two water return lines from my sump that are pointed at about a 45 degree angle to the front of the tank...
I then have a small rio pump and a small surge pump on the right side of my tank. one is up on top making the water ripple, and the other one is on the bottom pushing water behind my LR. they are both pointed so water flows to the left side... on the left i have a small powerhead on the bottom of the tank and pointed forward to the front of the tank...... the top left side of the tank is where the overflow is located.
but it really doesnt matter. just as long as you minimize any dead spots.....
i am planning on getting a few more powerheads.... i may put on some tubes to attach to them so i get two places that move water.. one, by the powerhead, that will suck in the water, and the other end of the tube, where the water pushes out... i figure if i get a foot or more of tube, per powerhead, it will be like having 1.5 times the waterflow....
i am also thinking putting powerheads on timers... have one set (a) angled to push water clockwise and the set (b) to go counter clockwise.......
have the time set up like follows. (lights come on at noon and off at midnight)
A B
I I 12:00 PM
I o 3:00 PM
o I 6:00 PM
I o 9:00 PM
o I 12:00 AM
I I 3:00 AM
o o 6:00 AM
o o 9:00 AM
I=on, o=off
but then again... i may just change my mine and do something different...... but i hope that gave you a few ideas... let me know what you come up with.. maybe i can incorporate your idea with one of mine..