Alternanthera reineckii

Alternanthera reineckii is a perennial herbaceous plant belonging to the Amaranthaceae family. Widely recognized in the aquarium hobby, it is prized for its vivid red and purple foliage, which provides a striking visual contrast to the green plants typical of freshwater aquatic landscapes.

Originating from the tropical regions of South America, specifically Brazil and Paraguay, this species naturally inhabits wetlands, riverbanks, and marshy areas. Its ability to thrive in both submerged and semi-emerged states makes it an excellent candidate for various aquatic environments and terrarium setups.

Botanically, it features a sturdy stem with opposite, lanceolate leaves. The plant exhibits high phenotypic plasticity based on its environment. Under strong lighting and with sufficient nutrient availability in the substrate, the leaves develop intense pigmentation, which is a key trait sought after by hobbyists.

Regarding agricultural requirements, Alternanthera reineckii needs temperatures ranging from 22 to 28 °C and a pH level between 6.0 and 7.5. Consistent CO2 injection is essential to maintain vigorous growth, while high-quality iron supplements in the substrate are mandatory to prevent chlorosis and ensure the leaves maintain their characteristic red hue.

The primary use is in aquascaping, where it is utilized as a midground or background plant to create focal points. Propagation is typically achieved through stem cuttings. Common issues include infestation by filamentous algae and stem rot, often triggered by poor water circulation or the sudden depletion of essential macronutrients.