Is there such a thing as too much flow?

I just bought a wave maker for my 29 gallon (FOWLR as of now) today. It was rated at 7500 LPH. At first I installed it on the side wall of my tank blowing directly to the other end, but then I realised that the current was too strong - sand was getting blown around and my clowns had to take refuge behind the rockwork because they couldn't swim against the current. I repositioned it so that it's now on the back wall of my tank and angled upwards. Half of the current now runs directly into a sturdy chunk of rock, effectively diffusing it. Since the current currently (hah) flows at an upwards angle, there's a lot of water surface movement. There's even this mini cyclone thing at the water's surface where the flow from the wave maker intersects the flow from the overhang filter.

Anyway, despite me having reduced the flow inside the tank, there's still this very turbulent zone where any fish that swim into it basically get blown away. I've watched my clowns try hard to swim against the current, only to get blown far away, but then they come back again and again. I'm worried that they may bump into something and get injured, or simply grow exhausted from using so much energy.

While the sand is no longer being blown everywhere, I still see a bit of movement in the sand in one particular corner of the tank; nothing too obvious, but if you watch closely you can see a few tiny grains scuttling along the sandbed.

So, do I have too much flow, or does that sound about right?