Water lettuce loves shade and floats with roots hanging down in the water. They multiply fast, but it's no trouble to pull out the older ones to let the younger ones grow. They can be invasive in public waterways, though, so either compost them or bag them for the trash.

Nancy, I like the water lettuce, but it's illegal in Tx so that won't be an option. Any other ideas?

Sorry to hear they're illegal in TX. They would be perfect. Parrots feather is pretty shade tolerant, and most varieties will float happily on the surface.

Well, I just ordered some water lettuce from an online store. The website showed it to be illegal in CA., but didn't mention Tx. I guess I'll wait and see if I get my plant!

Here is a link you might want to check out.

http://www.ntwgs.org/articles/illegalAquatics.html

Duckweed or frogbit perhaps