Alternanthera reineckii "Rosaefolia"

[unveränderte Übersetzung]

There are around 170 known species of the genus Alternanthera. Alternanthera reineckii was first imported into the Netherlands in 1965 under the name of Telenthera osiris. It is considered one of the few species in the genus that can grow entirely submersed. It originates from South America, where it is found along riversides in areas that are periodically flooded during the rainy season.

Over five different varietys are cultured. Alternanthera reineckii "Rosa", also sold under the trade names of "Alternanthera rosaefolia" and A. "pink", is a relatively easy cultivar and is the most widespread variety found in trade.

A. reineckii "Rosa" may be kept under low light and without additional CO2 fertilisation, however, it will never attain its full potential then. Medium to high light intensities (0.4-1 watt per litre) and fertilisation with CO2 provide it with ideal conditions.
In tanks with less intensive light, this plant tends to throw off its lower leaves. The water may be soft to hard, and the pH does not play a significant role either. However, the plant tends to do better in slightly acidic water.

Other than many red-pigmented plants, it prefers a nutrient-rich environment with high levels of nitrate (10mg/l and over) and phosphate (0.5 mg/l and over). In water with a lower nutrient content, fertilisation via the substrate may further the overall health of the plant and its speed of growth considerably.

When first planting, make sure you leave a certain distance between the stems. This species is easy to propagate by cuttings, just trimm off the shoot tip and replant into the substrate. On the leftover part of the stem, lateral shoots will soon start to grow, which makes the plant more bushy.

The purple colour of the leaf undersides makes A. reineckii "Rosa" a strong contrast to the manifold green aquatic plant species available in the trade, especially when it is planted in groups. Three to five strong shoots may be used for setting colour accents in the background.
In nature aquaria, this plant is not very widely spread. However, in Dutch tanks it is the most popular red plant.