We used lighting grid, each little square was about 3/4s of an inch big. We
spray painted it black and then stuck a sprig of watercress through each grid.
The stuff grew like crazy and even flowered. It had long roots that went down
into the screening media.
Then one of the labs walked across the grid and broke it in several large
places. I tossed it all and replaced it with water hyacinth.



k30a