Rotala indica
Rotala indica
Also known asIndian toothcup · Rotala 'Bonsai'
Water parameters
Light and nutrients
Substrate type: rooted. Propagation: stem cutting.
Substrate compatibility
| Substrate | pH effect | Nutrient load |
|---|---|---|
| Aquasoil (ADA Amazonia) | lowers pH | very high |
| Dirted tank (mineralized topsoil) (DIY soil substrate) | slightly acidic | very high |
| Mineralized clay substrate (Seachem Fluorite) | neutral / inert | moderate |
| Inert sand (Pool filter sand) | neutral / inert | none |
| Inert gravel (Aquarium gravel) | neutral / inert | none |
With fish
Origin and habitat
A small semiaquatic stem plant of the loosestrife family, Lythraceae, Rotala indica (Willd.) Koehne, the Indian toothcup, native to tropical Asia in Bangladesh, India, Thailand and Myanmar, in marshes, rice paddies and shallow water. True R. indica, also sold as Rotala 'Bonsai', is smaller and rounder-leaved than the much more common R. rotundifolia, with which it has long been confused; many plants traded as 'R. indica' are actually R. rotundifolia, and vice versa. Submerged leaves are thin and oval, green to pinkish under good light, while the emersed nursery form has rounder succulent leaves. Beyond the aquarium it is a notorious rice-field weed, introduced and naturalised in Italy, Portugal, the Congo and the rice regions of California and Louisiana, where its prolific seeding makes it a problem.
Care notes
Easy to moderate. It grows in low to high light, with or without CO2, but looks best under moderate to strong light with CO2, where it stays compact with three or four leaves per node and takes on pink tones; in low light it has only two leaves per node and the stems stretch leggy. Plant in groups of five to ten, trim the tops and replant, and the cut stems throw side shoots. The change from round emersed nursery leaves to thin submerged ones takes a week or two, with old leaves often dropping first. Feed moderate nutrients with iron and potassium to support the pink colour. Keep it around 22–28°C in soft to moderately hard water. It is a good entry into Rotala without the demands of R. macrandra or R. wallichii. Because it seeds so freely and is an established crop weed, never release it or dump tank water outdoors. It is an ornamental, not a crop, so it is unsuited to media-bed aquaponics or hydroponics.