How much circulation in 90

[Wfate]

Gallon reef with fish. I am thinking of buying two 450GPH circulating pumps for flow in the tank.
Should I do one big one or two smaller ones? How much flow should I have? (ballpark)

 

[slitherbomb]

I have two 1300gph power heads in my 75 soo.......

 

[Gubernaculum86]

I have 2 750's, a skimmer that's supposed to be rated at 500gph and a canister that's rated at around 300gph