Elodea
America and is often confused with Brazilian elodea (Egeria densa), which was introduced from South 1 America. Both are found in similar habitats, and both were spread throughout their range by way of the aquarium trade. Elodea is a perennial and prefers quiet, still and fresh to slightly brackish waters. It is a prolific producer of oxygen and can grow into some of the thickest mats of aquatic vegetation in North America.