The leaves can take on various shades of red under bright light, but the red roots are the most striking feature of this plant. The growth rate is not as fast as Duckweed, Azolla, Salvinia and other invasive floating plants, but it does reproduce easily and with no effort in the aquarium. Light is usually not an issue for any floating plant in the aquarium because of how close it is to the light in the aquarium, out doors it is more critical as the plant does not tolerate shade. It will not survive cold climates or freezing temps. I do not know why whoever wrote the original write up deemed it has difficult to grow. As a pond plant it may be more difficult or impossible in cold climates. It may be interesting to note that the plant has recently been found growing in parts of Florida, and as a result there is a push to declare this plant invasive. Any non native plant found growing anywhere in the USA is subject to such classification regardless of any proven or unproven risks it may impose.
I have noticed that this plant does not like surface agitation. The leaves tend to sink and decay if it gets jostled about. Isolate a section of the surface and the plant will reproduce quickly and flower.
This stuff grows very, very fast! I grow it in high tech, low tech, no tech, it even grows for me at the office in a bowl with no light except the overhead incandescent! Mostly herbivore proof, just as tough as anubias, though do expect the occasional hole and tear when keeping with herbivores as with any other plant! I got this off aquabid shipped for 5$.
I purchased this plant and some water lettuce and the fluitans did not propagate, in fact it died off. I think it may have been a bit of a bio-chemical war between the two and the fluitans lost. Also, I kept it in high surface agitation. That may have played a part too. A beautiful plant with wonderful root systems though!