Hello Codi,
Thanks for the welcome. I have never done Ap any other way. I think the advantage of pea gravel is that it filters the water while providing O2 as the water is flushed thru and back to the tank. No need to get rid of the solids as the beds become a little eco system with worms to eat the left overs. More closed loop in that you just feed the fish and eat the veggies.
All sorts of ways of doing it. The least amount of work or daily involvement would be my choice.
How do you handle solids then? Inject O2 at all?