Powerhead flow rate?

[leafyseadragon]

I am setting up my fish-only, live rock tank this week. The skimmer (Bak-Pak 2R) doesn't seem to move much water around, so would a powerhead to circulate the water be a good idea? And if so, what kind of flow rate should I be looking for? The tank is a 37 tall.

 

[Guest]

I believe the formula is 10 times the water flow? so around 400gph is a good choice...