I too create a circular flow of water. I have 2 koralia nano 240's in my 25g. One on the left pointing up, and one on the right pointing down. My inflow pipe is below the left koralia, and my outflow spraybar is vertical near the one on the right. Optimally, you want the water flow to bounce off of the glass, creating a more subtle, but wider movement. You also want your plants to sway slightly, almost like wind moving through them.