I dont know if you've ever swam in the ocean or not near a reef, but it is certainly not just a one way laminar flow. It goes back and forth and over and under and is turbulent, so try to replicate that in your aquarium. Place powerheads on each side of the tank and aim them at each other, that way there isnt just a steady current pulling through your tank but instead a turbulent mess that the fish can swim through and keep them on their toes, so to speak.
They handle it surprisingly well, I had four Koralia 4's and two 3's in my tank, plus my large return pump and and no fish at all even acted like it was having issues swimming, plus for the most part they never even looked like they were getting blown around. I would feed and be able to tell from watching the food that the water was getting mixed well, but the fish go right on through it like it's pretty calm.
Anyway, that's my recommendation, do with it what you will. I try to always replicate the way the ocean behaves, whereas the way you have it set up is more like living in a river.