Plumbing TLF Reactors - Waterflow Together or Seperate?

[FishyFishy!]

I use a maxi-jet 1200 with the two supplied ball valves from TLF to control flow with the left setup running.

With the setup on the right, you could obviously swap the carbon and the GFO so that it goes into the carbon chamber first. Would it even make a difference if the carbon or GFO was first? (other than the breakdown of the GFO if it tumbling too fast).