kien's 150g Room Divider Mixed Reef & Stuff

[JDigital]

I think you above illistration will work just fine... why? because I assume most of your rockwork with be down the middle of the tank, so unless you want direct flow blasting your rockwork/corals at that end of the tank, I think you will be just fine with 2x mp40's positioned like your pic. Remeber Vortechs have a nice wide flow pattern... plus you will have your 2 returns (which I assume are adjustable for direction) and the K4 at the other end of the tank, which you could mount in the middle...