I don't think you have to remake this... I think you need to add a reactor bypass so you can reduce the flow through the reactor without limiting the water flow to the tank.
Here's what I would do: put tee barbs on the reactor in and out, then connect them with some tubing and a ball valve.
View attachment 1035964
You can then use the ball valve to tune the flow through the reactor.
I've seen that, but wasn't sure if it would work here properly. I suppose I'd need to find some really big tees as to not restrict flow there. Also, don't I need another valve at the base of the reactor in order to create backpressure in the reactor? I thought maybe if I do that with the reduced connector that I have in addition to the bypass that you have suggested would be best? I've read that backpressure significantly increases absorption. Where does one find a ball valve like that, anyway? I didn't see them at Lowes. I have 5/8" ID tubing.