elodea

Sounds like the beautiful peasant girl in Don Quixote.

Elodea is a marvelous water plant that grows while you watch it. Oxygen bubbles stream from clumps of elodea sitting under the June sun, water split into oxygen and hydrogen, the mischief that allowed aerobic critters to arise a billion or two years ago.

I have elodea in a bucket outside. It survived the winter keeping worms and snails and ostracods company wiling away the wintry months under fluorescent lights.

In the science department, we spent a lot of time debating how much light elodea needed to survive. We'd buy clumps of it, then watch it slowly die in our classrooms.

What bothered me was that my elodea survived outside event through November, until the ice formed. And it's plenty dark in November.

I suspected the chlorine in the tap water. I still do. Chlorine is not good. Chlorine and TNT recently made the headlines. Chlorine damages more than just elodea.