Canadian waterweed, American waterweed, Anacharis canadensis, Pondweed
Family
Hydrocharitaceae (frogbit family)
Origin
Most of North America; introduced in Europe (including GB since 1841), Asia, Africa and Oceania
Water
freshwater
Temperature
10–25°C
pH
6.5–8.5
Hardness
8–20 dGH
Care level
beginner
Lighting
Moderate to bright light; CO2 not needed
Care
A submerged waterweed native to most of North America. It has bright green leaves 6–17 mm long in whorls of three on brittle stems that keep growing at the tips; a single plant can reach 3 m or more. Only its tiny flowers reach the surface. It grows in rivers and lakes, mainly in lime-rich water, and needs summer water temperatures of about 10–25 °C and moderate to bright light. That makes it a good plant for ponds and unheated coldwater tanks, but it suits warm tropical tanks poorly. Plant it in bunches at the back or let it float. The pH and hardness figures are our estimate based on its liking for lime-rich water. Never release this plant or dispose of it in drains or waterways; it is invasive in some countries. It has spread across Europe, Asia, Africa and Oceania and has been abundant in Great Britain and Ireland since the mid-1800s; in ponds and slow rivers it can choke the water. Sources: Wikipedia (en.wikipedia.org/wiki/Elodeacanadensis); Wikipedia, List of freshwater aquarium plant species. Checked October 2026.
Breeding
Propagated by cuttings: plant stem pieces in bunches or let them float until they root. Fragments root very easily.
Compatibility and tank mates
Goldfish, koi and plant-eating snails eat it, though it often grows fast enough to cope. Ideal for coldwater tanks and ponds; poor in warm tropical tanks.
Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.
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Items are sold by auction, buy it now or classified advert, by hobbyist and business sellers in the UK.
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Live fish and other vertebrates must be sent by specialist live-animal couriers (for example APC Overnight or DX Express), never by Royal Mail. Some invertebrates and plants may go by Royal Mail Special Delivery or 1st Class within its rules.
Banned and invasive species (for example those on the GB invasive species lists) cannot be listed, and sellers must meet the site’s animal welfare standards.
Members must be 16 or over to buy (16 and 17-year-olds with a parent or guardian’s agreement); sellers must be 18 or over.
Business sellers show their address, company details and pet-selling licence to buyers. Seller ratings run from 0 to 100: +1 for each positive feedback, −1 for each negative.
The site includes a free community species wiki with care guides (water parameters, tank size, diet, temperament, breeding).
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