Eleocharis parvula

Eleocharis parvula has a near-cosmopolitan distribution, occurring naturally on muddy and sandy banks of streams, ponds, and lake shores across temperate and tropical regions on multiple continents. This broad natural range accounts for its adaptability to a wide range of water temperatures and conditions. Submerged, it develops thin, cylindrical, bright-green blades reaching up to 10 cm in height, spreading horizontally through a network of fine, pale runners that colonise the substrate systematically. The characteristic lawn-like growth is one of the most iconic looks in planted aquarium design, synonymous with the Takashi Amano aesthetic. Eleocharis parvula is moderately demanding: it grows well with CO2 supplementation and moderate-to-high lighting, but can survive at lower tech levels with slower, less dense coverage. Fine-grained substrate such as Amazonia aqua soil or similar nutrient-rich products significantly accelerate establishment. Without adequate light reaching the substrate, the blades become elongated and floppy rather than forming a tight mat. In the aquarium it provides grazing habitat for small invertebrates and fish while contributing to a sense of natural scale.

Placement Plant in the foreground in small clusters of 5–10 blades, 2–3 cm apart. Runners will fill in the gaps over 4–8 weeks. Use tweezers to plant precisely and avoid burying the base too deeply.

Lighting Moderate-to-high lighting reaching the substrate level (40–80 PAR at substrate) is critical. The blades must receive adequate light to spread horizontally rather than stretching upward.

CO2 & Fertilisation CO2 injection at 20–30 ppm greatly accelerates runner production and coverage. Root tabs or a nutrient-rich substrate provide essential nutrition. Liquid fertiliser with potassium and iron prevents yellowing.

Propagation Propagates naturally via runners. Spread can be encouraged by pressing runners into substrate using tweezers. Individual runners can be transplanted to fill bare patches. New growth emerges from nodes along each runner.

Trimming Trim the lawn to 3–5 cm height using aquascaping scissors. Regular trimming every 3–4 weeks prevents the grass from becoming too tall and matted. Thinning overly dense areas prevents dead zones forming beneath the surface layer.