Is you return pointing down the tank? If so I would just try one pump at the other end and on a timer, this will give some randomish flow. If your return is going into a spray bar, or is small, etc i.e. not creating significant flow itself, I would add another pump also on a timer.
I think most people that use pumps place them where they can be seen least and have best affect. It's hard to judge how your anemone will react to the flow and light, it will move itself to be where it wants, the best you can do is have an idea what it will like and try and create this where you want it to end up. Then cross fingers.