well then i would ditch the oceans motions and go with two tunze 6000 on a multicontroller. it will allow one to turn off all flow at feeding or picture taking time with the press of one button. You can put them on a ups power supply, so if power goes out you have water movement, and that alone will last you for a while. Using the tunze's will allow you to go with a low gph return pump which will be more energy efficient. the 6000s are easily upgradeable to the 6100s with the $80 transformer,
1200 gph through an overflow is alot, ive got 1000 gph on my 180 and it is more than enough to keep the system turned over. i have even less on my 90, a 500gph return pump also feeds a refugium and a phsoban reactor, so i figure im getting maybe 250 through my overflow, which is right on target to feed my asmg3. since i have slowed it down by feeding the refugium and reactor on the same pump by skimmer is getting full once a week or less. i think it has been the single best thing i have done to improve my water clarity. I am determined to make my reef work the most efficiently it can, which can be hard with bright lights, but i am trying.
and for the record, i don't have anything against the oceans motions products, and i would use them on a closed loop. For my tank on a return with head pressure I use the lowest wattage pump i can , and thus flow just enough into the skimmer to maximize its performance.
