tank flow vs sump flow

MY tank right now has a 30 gal sump/fuge with a mag 18 pumping the return. The problems I have had with this is #1 the micro bubbles and #2 too much flow for the fuge. So I have been thinking to solve this what If i replaced the mag 18 with a mag 9 or 12 and added a tunze in the tank for flow. I mean when you think about it my mag 18 splits into 2 returns after head loss I get about 650 gph flow on each side. With a tunze I would get flow through out the tank and still have the surface being skimmed down to the sump/refugium. Then again the only reason I have a fuge is for pods and macro as an extra filter, does macro really even provide additional filtration that is word having?
My tank is 75 gal and the sump is 30.

 

I have a 30g sump/fuge and use a Rio hyperflow 12 at 720gph and have no problems.

 

Well im using a mag 18 @ 1800 gph so its a little difference

 

1800gph running through your sump is probably your problem.