Waterflow question

[c1ownfish]

I am upgrading my 55 FOWLR to a reef tank... I have purchased two maxi-jet 900's to increase water flow... My return from my sump comes in at the back right of the tank... I think it is a rio 1700...also have a small rio in that corner... Where should I put the two 900's and where should the majority of the water be directed??

Thanks!!