Wasser, please correct me if I'm way off base.
It almost sounds like an adaptation of the miracle grow fertilizer my wife uses on her flower garden. Instead of a hose providing the water it would be flow from the filter output.
If it's not,
Sorry it's the closest adaptation to what I think you are describing that I can think of in the real world.
Sorry just read this:
Originally Posted by Wasserpest
Not quite... I am hoping that the concentrated solution dilutes in the surrounding water passively, without any help from spraybars.
Guess I'm off.