Make sense. Thanks. I was just intrigued by the powerful return flow visible in the big tanks of some fish stores.That probably plenty of pump already if your sump and fuge are in a stand under the display tank. More flow through those tanks doesn't necessarily mean better.
Skimmers and macro algae tend to perform better with slower flow and more contact time with the dirty water.
3-5 times turnover rate for sumps and refugiums is plenty and usually means the system runs quieter.
If you just want more flow in the tank that's best done with power heads.
not to sure now! I'm amazed by the harmonious water movement that you see in these professional tanks equipped with the Vor Tec (spelling?) pumps....were you witnessing return flow or water movement within the tank