Bill do you know if your neighbor's lettuce is growing in water that has been filtered in his hydroponics set up? Also I have read that a growing medium even like coarse rocks will collect the particles and let them break them down so the nutrients can be used by the roots.
Adirondack I have one of those cheap underwater camera that I was going to use to take pictures last year under my raft of the one plant root, and to see if minnows were feeding off the bottom of the raft, and if fat head minnow were spawning on the underside, but the water quality with the tannin I have didn't seem like a good idea. But the one flowering plant I did have set up with the roots dangling so I could pull the cup out periodically and inspect the roots. That plant at first did grow just like the others and it's long dangling roots were white. Then in a few weeks the growth slowed down and started to die and the roots turned black. Later I inspected the plant and the roots completely rotted off.
