Brazilian microsword mentioned by SinCrisis is scientificallyLilaeopsis brasiliensis
, not to be confused with the more common "swords" such as those species in the genera Echinodorus
. I'm attaching a photo, as this plant is not in our plant profiles (yet). I have not personally had this plant, can't find it locally, but my sources confirm SinCrisis on it requiring moderate light and showing very slow growth.
Another very similar though slightly larger plant is the Pygmy chain sword
, formerly Echinodorus tenellus
but now deemed to be in Helanthium
, and it is in our profiles under the common name or Helanthium tenellum
, so a photo will be found there [click on the shaded name to see the profile]. There are several varieties under this common name, and depending upon which source there are 2 or up to 8 species. I have the narrow-leaf form in my 70g flooded Amazon forest tank, so I'm attaching a photo of that so you can see how it grows; it is the small plant across most of the substrate. The wide-leaf form is in my 115g Amazon riverscape tank and it grows much taller and obviously has wider leaves; it is perhaps Helanthium quadricostatus
or H. bolivianus
depending upon sources. [The Echinodorus and Helanthium genera have been the subject of several scientific studies using DNA and cladistic methods with the result that the classification is undergoing monumental changes.] Whichever the species, these plants grow very fast once settled; I am pulling out plantlets and runners every other week. In my former 90g flooded Amazon tank, of which there are photos under "Aquariums" below my name on the left, I planted one Pygmy chain sword
and within 5-6 months it completely carpeted the substrate as shown in the photos.