I put several dump truck loads of old pvc pipe that I got from a pipe supply place from 6 to 12" c900 waterline, heavy wall pipe, I cut it with a chain saw into 4 ft chunks and just dumped it into the edge of the pond, I didnt have it in time to place it before the pond got full. the fish seam to love it, I catch fish in that area quite a bit. this is in anywhere from 3ft of water to 10 ft I would guess.

All the really good ideas I've ever had came to me while I was milking a cow.