Water Flow

I am using a Fluval 403 in my 55g. It comes with a spray bar that you attach
towards the top of the tank. I have been trying to get good water flow
without an exsesive amount of current. I like the idea of running the filter
at full blast to got good water changes between the tank and the filter. I
drilled out the SB to help cut down on the pressure comming form it.

Here's the problem, I have the inlet tube in the back left of the tank, with
the SB across the top. I have the exit holes turned towards the back of the
tank, one slightly up the otehr slightly down. If I throw a leaf in the
right side of the tank it just seems to float around in that end. 

Are any other that are using canisters using the spray bars or did you go to
a more conventional water return? I am injecting CO2 so I don't want alot of
water movement on the very top or have the SB break the water surface.