Anacharis, known as Brazilian water weed, in the species Elodea canadensis is characterized by dark green leaves that oxygenate the pond.
A native of South America, the plant has been introduced into Central and North America, Europe, and Australia, is known for it vigorous growth.
These plants can be grown easily from cuttings and will survive the winter. If you wish to add this to your pond, when purchasing ask for Elodea, figure on one bunch per square foot of pond surface area .
The plant is shade loving, turning yellow if in full sun. Shade it by adding floating plants, such as hyacinths (if legal in your part of the world) or water lilies. Tiny white flowers appear from the top of the stem reaching to the waters surface.
Your fish will eat Anacharis, but if you have enough it will multiply rapidly enough to keep up with what your fish consume.
These plants also act as a turtle "magnet" in garden ponds. A by product of this plant is that it will promote pond water quality by keeping algae in check acting as a natural filter.
Should you decide not to have fish or let your fish forage in the pond, Anacharis will keep your pond balanced and clean without adding any other filtration method.
The plant is hardy in zones 4 to 11. You should consider adding this plant species to your pond to improve its ecology, contributing to the overall look of the pond.