I like Scott's recommendation. More smaller pumps for a tank like that.

The volume of flow would be fine, but the type of flow is just as important. With mutliple PH's that is a heck of a lot easier!

Well, I bought a #1 and put it in my tank.  I think that is sufficient for now.  I am also getting flow from my remora skimmer, Aqua Clear 70, and MJ600.  Things are moving around quite nicely now.

I just added  yesterday a Koralia #4 to my tank-- 125G...

I now have the sump return (700 gph), 2 Seio 1500s (1500 GPH each)-- one on the controller alternating 50% to 100% every 2 minutes, and then the Koralia 4 (1200 GPH) I just added yesterday as I had a bit of a dead area on one side.... getting good flow now-- I had several dead areas before it.

although I'm now running 4900 GPH on the tank (39x tank volume)-- it isn't as much flow as you think if anything I need to add another small powerhead behind the rock in the left rear corner or at least remove/move some of my rock and eliminate the dead spot.

I do like the koralia but it is a bit bigger then I thought it would be-- is is a bit more intrusive then my SEIOs IMO (I have them hanging "tunze style") .. although it does look better.

I do like the flow to power ratio for this thing-- just sips energy-- draws just 8 watts but puts out 1200 GPH.... the SEIOS draw 20 watts for 1500 gallons if I remember correctly.