Alternanthera reineckii 'Rosaefolia'
Alternanthera reineckii 'Rosaefolia'
Also known asPink alternanthera · Rosa · Telanthera (old trade name)
Water parameters
Light and nutrients
Substrate type: nutrient preferred. Propagation: stem cuttings.
Substrate compatibility
| Substrate | pH effect | Nutrient load |
|---|---|---|
| Aquasoil (ADA Amazonia) | lowers pH | very high |
| Mineralized clay substrate (Seachem Fluorite) | neutral / inert | moderate |
| Dirted tank (mineralized topsoil) (DIY soil substrate) | slightly acidic | very high |
| Inert sand (Pool filter sand) | neutral / inert | none |
With fish
Origin and habitat
A cultivated variety of Alternanthera reineckii (Briq., 1899; family Amaranthaceae), whose wild parent grows on seasonally flooded ground from Bolivia through Brazil and into northern Argentina. The species reached the European aquarium trade in the Netherlands around 1965 under the old name Telanthera osiris, and 'Rosaefolia', also sold as 'Rosa', became the most widespread named form in the hobby, valued in Dutch-style aquascapes for its pink-to-red colour. Grown emersed on the farm it shows green leaves with reddish undersides; submersed and under strong light the leaves turn light pink to deep magenta-red. Most stock now comes from sterile tissue culture, which keeps it free of pests and algae. After planting, the switch from emersed to submersed growth takes a few weeks, with some old leaves shed before new submersed foliage appears.
Care notes
Despite being a red plant, 'Rosaefolia' is usually rated one of the easier ones and is more forgiving of low CO2 than the standard Alternanthera reineckii, growing acceptably with or without injected carbon dioxide, the opposite of the older belief that it is the more demanding form. Even so, colour still depends on light, iron and nutrients. Bright light brings out the pink and magenta and keeps the lower stem from going bare, while dim light fades it toward olive. Iron matters for all the red plants here, with deficiency showing first as pale new leaves, so dose iron and potassium and use a nutrient-rich substrate or root tabs. Unlike some red plants that are starved of nitrate to redden, this cultivar actually prefers a nutrient-rich, higher-nitrate setting, around 10 mg/L or more of nitrate with adequate phosphate. CO2 near 20 to 30 ppm with strong light gives the most vivid colour and faster growth. Trim and replant the tops every few weeks to keep it bushy; the cut stems throw side shoots within a week or two. Propagate by stem cuttings, replanting the top 10–15 cm, and plant in groups of five or more for impact. It is an ornamental submersed plant, not a crop, so it is unsuited to media-bed aquaponics or hydroponics.