[leveldrummer]

the other thread you posted is indeed the way things seem to be moving in the hobby, lots of people at studying flow right now, and finding out that a couple powerheads at the top of the tank, on one side, facing the same direction, will push water across the top, it will hit the opposite wall, travel down and under creating a large circular motion, and with just 2 small powerheads, you can create enough flow to keep anything, putting 2 large powerheads across from each oether, pointing at each other, creates alot of turbulence, which is good, but uses alot of energy, studies are showing that a constant flow across the reef face. for maybe a few minutes, and then a current switch (wave maker timer or etc) is much easier to achieve and cost effective, and is just as good, if not better, for corals