Elodea (syn. Anacharis) is a genus of aquatic plants often called the water weeds. Elodea is native to North America and it is also widely used as aquarium vegetation. The introduction of some species of Elodea into waterways in parts of Europe, Australia, Africa, Asia, and New Zealand has created a significant problem, and it is now considered a noxious weed in these areasElodea canadensis, sometimes called American or Canadian water weed/pond weed is widely known as the generic water weed. The use of these names causes it to be confused with similar-looking non-native plants, like Brazilian elodea (Egeria densa) or hydrilla (Hydrilla verticillata). American water weed is an attractive aquarium plant, and is a good substitute for Brazilian elodea.The American water weed lives entirely underwater with the exception of small white flowers which bloom at the surface and are attached to the plant by delicate stalks. It produces winter buds from the stem tips that overwinter on the lake bo