Vallisneria gigantea

Vallisneria gigantea is native to the Philippines and parts of Southeast Asia, thriving in large rivers, lakes, and brackish coastal waterways where its leaves may reach 2 metres in length. In the aquarium, leaves grow to the surface and then sprawl across it, creating a dramatic canopy effect that diffuses light and provides shelter for surface-oriented fish. Despite its imposing size it requires no special chemistry — tolerating hard, alkaline water with ease — and grows vigorously under medium lighting without CO2. It is best reserved for tanks of 200 litres or more where its scale is appropriate. Regular pruning of the oldest leaves maintains a tidy presentation.

Light: Medium (30–60 PAR); grows well under standard T5 or LED community lighting. CO2: Not required; injection not recommended as it can accelerate growth to unmanageable levels. Fertilisation: Heavy root feeder — root tabs every 2–3 months; weekly liquid macronutrient dose. Placement: Plant singly or in small groups at the very back or corners of large aquariums. Propagation: Produces runners prolifically; daughter plants can be separated and replanted or removed to control spread.