Powerhead direction help?

[sailfin tang]

Installing a couple of powerheads tonight to add flow to my young reef tank.
I have been told to aim them at each other to create turbulence.
I was thinking on putting them on the back top at either end and aim them towards the middle top front.
Please let me know what would be best.
48" tank 80 gallon bow
Hydor Koralia 2 (2 pumps)

 

[sudc]

I would have them on opposite sides. One pointing up for surface agitation and the other either pointing to the front or back of the tank. That should give you decent flow and turbulence.

 

[dw62]

I agree on opposite sides with only two. It's also good to point them towards a glass side, so the flow can bounce around in the tank creating a random flow.