Surfsteve, the plant is looking yellowish. I added some fertilizer into the mixture, maybe too much. I stuck my finger down into the medium and it was wet, so it is getting water. Maybe too much. Getting the right kind of plant is probably critical.
What I am thinking could be tried is taking a square of rubber neoprene 1/4" or 7 MM and slicing some + slits in it to hold seeds or already started plants to be inserted into the + and then laying the neoprene on the water. It would float but yet always be moist and the roots would quickly grow into the water. If the plants would grow too heavy and sink the neo. then perhaps a hula hoop with a water noodle threaded onto it and the neo. in between. Or something to hold the plants in between and it would be a floating island. The noodle/hula hoop with a net hanging in between might be used for fish cage culture also. I was looking at the noodle/hula at Walmart yesterday and a floating hoop could be put together for maybe $5 or a little more.
