Elodea canadensis
Similar to Egeria densa Planch.
Brazilian Elodea can be confused with American waterweed (Elodea canadensis) which is a commonly occurring native species.
Brazilian Elodea is a very bushy plant with dense whorls of bright green leaves (except when growing in insufficient light, in which case the leaves are widely spaced). Brazilian elodea usually has four leaves per whorl (and each leaf is at least 0.8 in. (2 cm) long)
American Waterweed is smaller than Brazilian waterweed and generally has three leaves per whorl. Each leaf is generally less than 0.4 in. (1 cm) long. Neither Brazilian nor American waterweed produce tubers.