• Scientific name: Vallisneria spiralis
• Synonym: Vallisneria aethiopica; V caulescens; V. gracilis; V. jacquinii; V. pusilla; V. linne
• Common name: Straight vallisneria
• Family: Hydrocarithaceae
• Group: Aquarium plants
• Max height: 80 cm
• Distribution: Southern Europe and North Africa. Now introduced to many tropical and subtropical countries around the world.
• Habitat: Often inhabits nutrient-rich, stagnant or slow-moving waters.
• Substrate: Fine-grained sand
• Placement in aquarium: Background or at the edges of the aquarium.
• Planting density: 4-5 plants for 25 cm²
• Lighting needs: Bright
• Temperature: 20-27 °C
• pH: 6,5-7
• Hardness: 4-12 NK°

Description: Straight vallisneria is one of the best known and most popular of the vallisneria family. The linear grasslike leaves - 4-8 mm wide and pale to mid green colour - are arranged in a rosette. The leaves may grow to 80 cm in length and should be used as background planting or placed around the corners and edges of the aquarium. The flowers are borne on a long, tightly spiralled stem, from which the plant derives its common name. The plant will grow quickly and produce numerous daughter plants from runners. It can be kept in a wide range of aquarium conditions and in coldwater aquariums. Vallisneria spiralis prefers alkaline, medium-hard to hard water rich in carbonates. Vallisneria species are occasionally confused with Sagittaria species. For differentiation Vallisneria have fine thin roots, Sagittaria rough thick ones.