Vallisneria gracilis

Vallisneria gracilis is a relatively new addition to the aquarium hobby and comes from North Australia. In the habitat it only reaches heights of around 15 cm. In aquariums it can grow to a height of around 70 - 80 cm. For many years, the name Vallisneria gracilis was regarded as a synonym of Vallisneria nana, and the aquarium plant is still widely known by the latter name. However, more recent investigations have shown that Vallisneria gracilis should be distinguished as a separate species from V. nana. True Vallisneria nana, also an Australian species, is a very variable, larger plant with broader leaves and is more similar to Vallisneria spiralis.

Its light green ribbon-shaped rosulate leaves growing make V. nana a great contrast plant for the middle- as well as for the background of a tank. Once established, V. gracilis forms many runners. The chains of plants that are thus created sometimes form dense curtains that can cover the entire back of the tank.

In contrast to other Vallisneria species, V. gracilis is a little more demanding regarding light intensity. Its ideal range starts at 0.4 watt/l and above. If light intensity is lower, or if the individual plants grow very densely and thus take light away from each other, the leaves of V. gracilis grow out long, which in turn can influence the light intensity for other plants in the tank as well as their nutrient supply.

Regular fertilisation with liquid iron fertiliser and CO2 injection are recommendable as they further growth significantly. If its few demands are satisfied, V. gracilis is an uncomplicated aquarium plant that reproduces readily.