Trouble shooting 6000

The single controller will allow you to lower the flow rate to as little as 30% then back up to 100% (or lower) to create a wave motion. You can also adjust the flow manually on the transformer/driver box of your stream 6000 without the controller.
I wouldn't worry- all the animals will adjust. This flow is more like what they receive in the wild and will cause no harm. You can lower the flow with a jewelers screwdriver on the left side of the blue driver box is the adjustment.