Question 2, water flow and designs for reef tanks

[DanG]

More flow is good, but if it should be balanced. There's little point in having 5000gph through the middle of the tank and a bunch of dead spots that allow nusiance algae to grow. From that point, a closed loop running 6 or 7 outlets would be a good choice because you would be able to direct some of the flow.
Newer powerheads are a good choice for smaller or non drilled tanks because they can produce a lot of flow (tunze nanostream) with very low power.