Pygmy chain sword
Helanthium tenellum
Also known asNarrow leaf chain sword · Dwarf chain sword
Water parameters
Light and nutrients
Substrate type: nutrient preferred. Propagation: runners.
Substrate compatibility
| Substrate | pH effect | Nutrient load |
|---|---|---|
| Aquasoil (ADA Amazonia) | lowers pH | very high |
| Mineralized clay substrate (Seachem Fluorite) | neutral / inert | moderate |
| Dirted tank (mineralized topsoil) (DIY soil substrate) | slightly acidic | very high |
| Inert sand (Pool filter sand) | neutral / inert | none |
With fish
Origin and habitat
Native to the Americas, from the southeastern United States south through Central America to Brazil and Argentina. The species (Echinodorus tenellus, sometimes reclassified as Helanthium tenellum) is the smallest Echinodorus, forming grass-like rosettes only 3–10 cm tall. In the wild, it grows in shallow pond margins, seasonal wet meadows, and tidal freshwater flats. The plant spreads by runners, similar to dwarf sagittaria, forming dense carpets of narrow, grass-like leaves. Several trade forms exist: the green standard form and a reddish variant that develops pinkish-red coloring under strong light. One of the few Echinodorus species small enough for foreground use.
Care notes
An easy to moderate carpeting plant that grows in both low-tech and high-tech setups. Under high light with CO2, Echinodorus tenellus stays short (3–5 cm) and carpets rapidly, producing a lawn-like foreground. Under low light without CO2, growth is slower and taller (5–10 cm), eventually forming a midground ground cover. The red variant requires moderate to high light for coloring; under low light it reverts to green. Plant small portions 2–3 cm apart. Root tabs or nutrient-rich substrate improves growth rate and density. Once the runner network establishes, the carpet is self-sustaining and fills in gaps quickly. Trim the top of the carpet to control height. Temperature: 18–28°C. pH 6.0-7.5. Soft to moderately hard water. Propagation is automatic via runners, similar to dwarf sagittaria. The main advantage over dwarf sagittaria is the shorter growth habit under high light, and the availability of the red color form. The main disadvantage is slightly higher light requirements for optimal performance. A good carpeting choice for medium-tech tanks with CO2. Compatible with all community fish. The grass-like leaves provide shelter for bottom-dwelling species and fry. In low-tech setups, combine with dwarf sagittaria for a varied, natural-looking ground cover that doesn't require CO2. Available as tissue culture cups from most aquatic plant retailers.