Alternanthera lilacina

Alternanthera lilacina is a rare and prized aquatic stem plant from South America, valued for its highly unusual lilac-to-purple leaf coloration that is genuinely uncommon among aquatic stem plants and makes it a standout accent piece in any planted aquarium layout. The oval to lance-shaped leaves are soft in texture and grow in opposite pairs along upright stems. High light, CO₂ injection, and regular phosphate dosing are all recommended to sustain the distinctive purple tones that make this species special.

Plant in nutrient-rich substrate under very high-intensity lighting (50+ PAR). CO₂ injection at 25–35 ppm is required — without CO₂ the purple coloration will fade to pale green. Dose phosphate specifically — phosphate deficiency is the most common cause of colour loss in this species. Regular trimming encourages compact, bushy growth. Soft, slightly acidic water (pH 6.0–7.0) produces the best colour.