Vallisneria giganthea is the giant form of Vallisneria, producing exceptionally long, broad, ribbon-like leaves in vivid bright green that can reach one metre or more in length in a large aquarium. When planted in the background of a tall aquarium, the leaves billow and sway across the upper water column in a flowing, naturalistic display that is unlike most other aquarium plants.
Despite its impressive size, it is an easy and tolerant plant growing well under low light without CO2 injection. It adapts to a broad range of water conditions including hard and alkaline water. It spreads by runners to form a large colony over time and grows strongly once established. Regular thinning is recommended in smaller set-ups to prevent it from dominating the layout.
Vallisneria giganthea is best suited to large aquariums from 150 litres upward where its eventual leaf length can be properly accommodated. For smaller tanks the nana or spiralis forms are better choices. In a large aquarium it creates an extraordinary flowing background effect that is one of the most dramatic in the freshwater hobby.