what are the conditions you plan to create for the trout to spawn?
i have considered progressing from a stocked trout pond to a self generating system.
besides cold aerated water flowing over gravel, what else is necessary?
how do the spawning fish reach the spawning area from the pond?
i guess at some point you restrict access to the spawning area to prevent predation?

i like your concept and look forward to hearing more of your ideas.

AP-thanks for your work educating us newbies. keep it coming.