The video didn't look like all that much flow to me.
Do you have sand blowing around - or is the fish being pummeled into the rocks?
Those would be signs of too much flow.
If you have too much flow you could try aiming the output at a rock. The flow will also go down once the wave maker gets gunked up a bit.
I have two wave makers on my small tank and have found the flow is too much even with both of them on low if I clean them both at the same time. So instead I clean one at a time, a month or so between cleanings so they're dirty most of the time.