so Ive made an above ground water garden to cultivate plants for my pond. Should I put heavy soil in the bottom? Rocks? Anything? Does anyone have any ideas? I plan to order some parrot feather, anacharis, mosaic, iris water lettuce, hyacinth, etc type plants and as they over grow the small water garden seperate them and put some in the bigger pond. That way my fish don’t kill all my plants all at once but still get to nibble on stuff from time to time and it will hopefully work as a secondary water clearing filter system. I’ve attatched some pics. It’s about three feet wide and two and a half feet tall and I buried it in the ground about 8 inches to help insulate it a bit. Anyone have any advice?