Recently added some Water Lilies, not doing as well as expected. Not sure what to make of this.

Planted the tubers in large pots 3 feet deep, they had a few leaves, a couple inches long at the time. A week later, leaves to the surface and more on the way, up to seven leaves each plant!
The leaves are red in color when growing and at the surface, but they didn't last a couple weeks before turning brown and disintegrating away.
Now leaves keep coming but, they seem to die shortly after reaching the surface.

The Lilies were removed from a small Lillie overcrowded backyard pond nearby. I looked at the pond they came from, clean healthy water, beautiful red flowers. The owner did not want to throw them away, so held them in a plastic container, and put them in the classifieds for free, not sure how long they were in the container.

Any input is appreciated.