Float plants that do not receive enough light may stretch producing a very thin/spindly stem.  Recovery
is unlikely and stretched plants retain the poor stem as they grow.  When the float system first started in
Kentucky back in the early 1990's some producer tried to produce plants in existing fiberglass greenhouses.
The typical old fiberglass greenhouse had yellowed to the point that light was an issue and stretched plants
were common in these type houses.  The plants in the picture below were grown in outside beds under
two layers of plant bed covers with one resting on the surface of the tray.