Indian Rotala

Few aquarium plants carry more wrong names than Rotala indica. The reddish stems sold under that name since the 1960s are mostly R. rotundifolia, while the genuine species spent years in the trade as 'Ammannia sp. Bonsai' and was only identified correctly in 2009. Its botanical name is Rotala indica (Willd.) Koehne, with Ameletia indica as a synonym.

The diagnostic feature is small and easy to check: a whitish, cartilaginous margin on leaves that are obovate to spatulate with a rounded tip. Submersed it grows strictly upright to about 20 cm on a thick, sparsely branched stem, and the shoot tip reddens where light is strong.

Flowgrow lists a working range of 22 to 28 °C and pH 5 to 7, with high light. Growth is only moderate and the light and nutrient demands are real, so it does better as a free-standing midground group than packed into a mass. Because so many plants travel under this name, it is worth buying from a source that knows which one it has.