2 inch Overflow Question

[Invigor]

a friend of mine uses 2 2" overflows for 6000gph

I was wanting to use a ampmaster 3000, for about 2800gph(after head pressure and stuff), but reefcentral says minimum size is 2.06" so I decided to go with 2 1.5"

so in theory, it should do around the 3000gph mark. you might have to turn down the pump a little