Cracker...
Let the games begin SPS require a vast amount of ever changing currents - ok sure, more so than total turnover but this is the easiest way to calculate how much you need (without getting into specific placement of powerheads) As I say, from what I have read this is at least 20 times the tank turnover per hour.
Why the need for high water velocity you ask? Predominantely to rid the coral of it's own wastes (which is true with any coral) Another key requirement for needing high water turnover (and high current) depends on the amount of SPS corals you keep. Large "heads" of acropora will significantly reduce the water flow about half way through a colony. This means the larger the (turbulent) movement of water the more chance it can satisfy SPS's current needs. IMO, even with most reef tanks we aren't even coming close to the water movements we see in nature!
A small quote I found from a reef web site:
RnB...
Dude, I have the pump but have not hooked it up yet (awaiting an Oceans Motions 4-way from the States) But, I must say I am very impressed. How can you be impressed when you haven't seen it working yet you ask? Simple, the design of the pump is solid with quality parts - very much the same look & feel as an Iwaki. The thing weighs almost 15 pounds!!! It's like looking over a Ferrari motor versus Toyota motor, you know quality when you see it