Canadian Waterweed

Canadian waterweed is a stem plant from North America that likes cool water and has spread to many parts of Europe since the 19th century. Its leaves are about 1 cm long, dark green and arranged in whorls of three along the stem. It has smaller leaves and is thinner than Egeria densa, with which it is often confused in the trade; in Egeria the leaves are 2–3 cm long and form whorls of four or five. It grows fast in unheated aquariums, goldfish tanks and garden ponds; above 24 °C it weakens.

Do not release into the wild: It is an invasive species that has spread into natural waters in Europe. Excess plants and trimmings should be dried and thrown in the trash.

• Bury the stems 4–5 cm deep in groups of 3–5; since its roots are weak, it can be held down with a weight for a while.
• It can also be grown floating freely without planting.

• Light: Moderate.
• CO₂: Not required.
• Temperature: Cool water; it is not suitable for tropical aquariums.
• Fertilizer: Usually not needed; it takes its nutrients from the water.
• Trimming: Because it grows fast it needs regular thinning; remove the excess from the aquarium.