Giant vallisneria (Vallisneria gigantea) care guide

Group
Plants
Other names
Giant val, Vallisneria 'Gigantea', Vallisneria americana (most plants sold under this name)
Family
Hydrocharitaceae (frogbit family)
Origin
Trade name; Tropica's stock comes from Asia
Water
freshwater
Maximum size
150 cm
Temperature
18–28°C
pH
6.5–8.5
Hardness
5–20 dGH
Care level
beginner
Lighting
Low to medium light; CO2 not needed

Care

Vallisneria gigantea is not an accepted species name. Wikipedia explains that it is a trade label for the largest Vallisneria forms, and that most plants sold under it are really V. americana, with some being V. spiralis. Tropica sells it as Vallisneria 'Gigantea'. We keep the trade name as the page key. These giant forms have tough leaves typically 50–150 cm long and about 2 cm wide, which reach the surface in most tanks and trail along it. Tropica rates it easy, with low light and CO2 needs and fast growth. It suits only large aquaria, as a background plant; prune the leaves regularly so they do not shade the plants below. Vallisneria generally prefers neutral to alkaline water, grows best in bright light but copes with moderate light, and does not need CO2. Plain gravel works if an iron-rich fertiliser is added now and then. Plant with the crown (where leaves meet roots) just above the substrate. Water figures are our estimate, not from the sources. Sources: Tropica (tropica.com/en/plants); Wikipedia (en.wikipedia.org/wiki/Vallisneria); Wikipedia, List of freshwater aquarium plant species. Checked October 2026.

Breeding

Spreads by runners from the base, each producing daughter plants along it. Once a daughter has its own roots, cut the runner and replant it elsewhere. Do not bury the crown when planting. It runners most freely in a nutrient-rich substrate.

Compatibility and tank mates

Tropica notes that the tough leaves are not normally eaten by herbivorous fish, which makes it a good choice for large tanks with big fish. Large diggers may still uproot young plants.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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