Alternanthera Reineckii 'Rosaefolia' - Immersed Potted Plant

Alternanthera Reineckii 'Rosaefolia' striking red stem plant prized for its pink-red to deep burgundy foliage and strong contrast against green aquascape plants. This cultivar is commonly associated with Alternanthera reineckii ‘Pink’, and is typically used as a colourful midground to background accent in planted aquariums.

Origin

• Species origin: South America
• Habitat: River margins, marshy zones and semi-aquatic habitats; one of the few Alternanthera commonly grown fully submerged in aquaria.

Physical characteristics

• Form: Upright stem plant with opposite leaves and branching growth after trimming.
• Leaf shape: Lanceolate to oval-lanceolate leaves, broader than very narrow red stems but slimmer than some broad-leaf varieties.
• Colour: Upper surfaces range from pink-red to reddish bronze; undersides are often distinctly pink. Stronger light improves red colouration.
• Height in aquaria: Commonly around 20–50 cm, depending on conditions and trimming style.

Aquarium requirements

Difficulty

• Level: Moderate
• It is not especially difficult to keep alive, but achieving the best colour, density and lower growth is much easier with stronger light, stable nutrients and CO₂.

Lighting

• Requirement: Medium–high to high light
• Bright light is important for strong red tones; in weaker light the plant tends to grow greener, leggier and less compact.

CO₂

• Demand: Medium
• It can survive without injected CO₂ in some setups, but CO₂ supplementation greatly improves growth rate, colour intensity and overall form.

Nutrients & substrate

• Substrate: Best in a nutrient-rich aquarium substrate, though it can also be grown in inert substrate with good fertilisation.
• Fertilisation: Responds well to complete fertilisation, especially micronutrients and iron, alongside steady macronutrients. Good fertiliser conditions are repeatedly noted as important for both growth and colour development.

Water parameters (guideline)

• Temperature: approximately 22–28 °C
• pH: mildly acidic to neutral is generally preferred
• Flow: Gentle to moderate, with good circulation helping keep leaves clean and growth stable.
  The most explicit temperature guidance in the sources places it in the tropical planted-tank range.

Planting & spacing

• Plant stems individually or in small groups with a little space between them so light can reach the lower leaves.
• Best used in the midground or background, especially in grouped plantings where the red colour creates a strong focal block.

Propagation

• Very easy to propagate from top cuttings.
• Trim healthy tops and replant them into the substrate; cutting the terminal bud also encourages the mother plant to form more side shoots and become bushier.

Maintenance

• Regular trimming is important to keep the group dense and attractive.
• Replanting the healthiest tops is often the best way to refresh older stems, especially if the lower portions become bare.
• Avoid frequent uprooting once planted, as rooted stability helps the plant establish more reliably.

Aquascaping use

• Excellent red accent for Dutch-style layouts, stem groups, and contrast planting among green species.
• Works best as a colour block rather than a single isolated stem.
• In smaller aquascapes it can be used in the midground; in larger tanks it often suits the background better.

Companion compatibility

• Suitable for peaceful planted aquaria with community fish and shrimp.
• Less suitable with strong diggers, rough herbivores or fish that constantly disturb rooted stems.
  This is an inference from its stem structure and planting habit rather than a direct species-specific claim in the sources.

Lifecycle & emersed form

• Can be grown both submerged and emersed.
• Emersed growth is usually sturdier and often easier during cultivation, while submerged growth develops the ornamental red foliage most aquascapers want in display tanks.

Common issues & diagnostics

• Weak colour / too green: Usually not enough light, insufficient micronutrients, or lack of CO₂.
• Leggy growth / bare lower stems: Common when light is too weak or when stems are packed too tightly and shade each other.
• Melt or rot after planting: Often linked to unstable parameters or major changes during transition from emersed to submerged growth.

Special features / benefits

• One of the most recognisable red aquarium stems for creating depth and contrast.
• Offers strong colour impact without needing to be an ultra-small specialist plant, and responds very well to careful trimming and high-tech planted-tank conditions.

Quick Specs (at a glance)

• Placement: Midground / Background
• Height: ~20–50 cm
• Light: Medium–high to High
• CO₂: Recommended
• Growth rate: Moderate
• Difficulty: Moderate