Power heads on opposite sides of the tank. For a fish only tank, you only need 550gph of flow. That doubles if your planning on a reef, and it goes up from there, if going SPS.
Two RW-8's is what you'll need to get the flow you need for your tank. 180-2100 gph. Perfect fit and those pumps are great. Ive used the rw4 and 8 and they havent let me down @Erick Merfeld
Yeah, one on each side. Set them at 50%. I think that'll be the sweet spot for your tank. I use the second mode on my rw4. its like an alternating pulse setting. @Erick Merfeld