Brazilian Micro Sword

Brazilian micro sword is the plant that fills the space between 'easy but coarse' foreground species and the demanding carpeting ones. The name in trade is Lilaeopsis brasiliensis, though Plants of the World Online treats that name as a synonym of Lilaeopsis minor, the accepted taxon for the plant sold as a foreground grass. Its leaves are narrow, sword-shaped and dark green, and it spreads by runners just under the substrate surface, so a few planted clumps grow into a continuous foreground over a season.

It comes from South America, from the floodplain and marsh habitats of Argentina, Brazil, Paraguay and Uruguay. It prefers cooler water than most carpeting plants: the sweet spot is 15 to 24 °C, which makes it a natural fit for tanks kept without a heater or for semi-temperate setups. pH of 6 to 7.5 and moderate hardness suit it well.

Moderate light keeps the runners tight and the growth compact. CO₂ helps it form a denser carpet but is not essential; without it the plant grows more slowly and the carpet stays a little looser. It grows emersed readily on damp substrate, which is useful for propagating a large foreground quickly before flooding the tank. In the aquarium, be patient: establishment is steady rather than fast.