"Just" filter out the roots... tee hee!
Have fun brah... I'm all set with filtering out the roots from a whole bedroom full of plants that this guy wants to run. Maybe on a tiny scale.
Hydroton is the ULTIMATE re-useable medium. I honestly don't think it ever goes bad; just dump it in a rubbermaid tote with tepid water and cannazyme, grab the root balls and swirl to release the pebbles, and let soak for a week until it starts to stink, then stick your res pump in there and pump out the water, replace with fresh water, pump out a couple times until the water runs clear, then re-fill and adjust to pH 6. Let sit until the pH appears stable and you are ready to rock n roll.