Heteranthera Zosterifolia

Heteranthera zosterifolia adds a light, lively green to the aquarium with its thin, grass-like bright green leaves, 3–5 cm long, arranged alternately along the stem. Because its leaves open like a star when seen from above, it is called "stargrass" in English.

Its growth form changes with light: in medium light it grows upright and becomes a full cluster in the midground to background. In strong light, however, the stems can spread horizontally close to the substrate and form a low, dense cover. It grows fast; it lives in an aquarium without CO₂, but becomes much denser and brighter with CO₂.

• Stems are planted in groups of 3–5, with 3–4 cm between groups.
• The lower leaves are removed and the stem is buried about 3 cm deep.
• In the midground it creates a strong color contrast next to red plants; it can also be used as a tall cluster in the background.

• Light: Medium; in strong light it grows lower and more spreading.
• CO₂: Not required, but beneficial.
• Fertilizer: Regular liquid fertilizer; because it grows fast, its nutrient demand is medium to high.
• Trimming: Trimmed often. It becomes bushier when cut from the top; stems spreading horizontally are cut back and tidied when they overstep their bounds.

It is easily propagated from top cuttings. Horizontally spreading stems root from their nodes; these can be separated to get new plants.

• Sparse stems with long internodes: Light is insufficient.
• Pale new leaves: Iron deficiency.
• Bare lower stems: When the cluster becomes too dense, the lower leaves get no light; thin out the cluster.
• Spreading across the surface: Stems that reach the surface shade the plants below; cut them regularly.