Description
Small foreground plants for aquariums are in short supply, but Helanthium tenellum (= Echinodorus tenellus) is one of the best. The submerged leaves are very narrow and light-, middle-, olive-green to reddish. It differs from the always light green Helanthium tenellum "parvulum" by darker, often reddish coloration and narrower leaves. The runners spread round the aquarium. A true "lawn'' effect appr.5-10 cm tall is only achieved at high light intensities, so you must make sure larger plants do not overshadow the plant. Plant individual plants a couple of centimetres apart (easiest with tweezers). A nutritious bottom promotes growth.
Helanthium tenellum, the pygmy chain sword, is still also known under its synonym Echinodorus tenellus. It is the smallest known species among the runner-forming sword plants, and rather variable. The variety usually found in trade originates from the American tropics. Its submersed leaves are very narrow, pointed, and of a medium to olive green or even reddish. They grow to a length of 6 to 10 cm, sometimes even longer, and a width of about 1.5 mm. Their widest part lies above the middle, around 2 cm below the tip. The submersed leaves of another form originating from North America (see Helanthium tenellum "parvulum"), though rarely cultivated today, has always light green leaves that are not as narrow, with around 2 mm width. They have their widest part below the middle.
Source
Flowgrow
Characteristic
Grasslike ground covering plant
Very narrow leaves
Olive green to reddish coloration
Spreads fast through runners
Complete Botanical Name
Helánthium tenéllum (Mart. ex Schult.f.) J.G.Sm.
Family
Alismataceae
Genus
Helanthium
Category
Middle Ground
Difficulty
medium
Growth
fast
pH Value
5-7
Temperature Tolerance
10-35℃
Carbonate Hardness
0-14 dKH
General Hardness
0-30 °dGH
Propagation
Runners
Can Grow Emersed?
yes
Aquascaping
forms a grass-like lawn
