Sump turnover rate vs tank turnover rate?

[Delphinus]

My own philosophy after having tried many different combinations over the years is that you don't really need a lot of sump volume turnover. Just the minimum (5x tank volume) IMHO, is fine, plus it leaves you open to any kind of flow possibilities in the main display (keep them independent). Leaving the high tank turnover within the tank itself leaves you open to turning off your sump return and the tank can still have flow.

The Tunze streams are butt ugly in my opinion but they're fabulous for moving a large fan shape volume of water and they're cheap as dirt to run.

Another option for a fan shape volume of water movement are the penductors on a closed loop, a little smaller and maybe a little less ugly but you need a decent size pressure rated pump to do it right.