Rotala sp. “Big Bear” — a beautiful and somewhat rare aquatic plant prized in aquascaping:

🌿 Basic Overview

• Scientific Name: Rotala sp. "Big Bear"

• Common Name: Rotala Big Bear

• Family: Lythraceae

• Origin: Believed to originate from Southeast Asia (exact locality uncertain — possibly Vietnam or Laos).

• Type: Stem plant (herbaceous aquatic plant)

🌱 Appearance

• Stem: Upright and moderately thick, capable of growing 20–40 cm tall.

• Leaves: Opposite, narrow to oval-shaped, typically larger and broader than Rotala rotundifolia.

• Coloration:

  • Under strong light and nutrient-rich conditions, leaves turn vivid red to deep pink.

  • In lower light, leaves appear green to light orange.

  • The plant displays excellent color contrast in aquascapes.

• Growth Form: Dense bushy clusters when regularly trimmed; fast vertical growth if left untouched.

💧 Tank Conditions

🌾 Growth & Maintenance

• Growth Rate: Medium to fast under ideal conditions.

• Pruning: Regular trimming promotes bushy, compact growth.

• Replanting: Cut stems can be replanted easily; they root quickly.

• Spacing: 2–3 cm between stems to allow light penetration.

• Position in Tank: Midground to background, depending on tank size.

🌈 Color Enhancement Tips

To achieve Big Bear’s signature deep red or pink coloration:

1. Provide high-intensity light (at least 0.8–1 W/L).

2. Ensure stable CO₂ injection (~20–30 ppm).

3. Use iron-rich fertilizers and balanced micronutrients.

4. Maintain low nitrates (5–10 ppm) and higher phosphates (1–2 ppm) — this enhances red pigmentation.

🧪 Propagation

• Method: Stem cuttings.

• Simply trim the top portion and replant it into the substrate.

• Roots develop within a few days under good conditions.

🌍 Aquascaping Use

• Often used as a focal red plant in Dutch and Nature-style aquascapes.

• Looks stunning in contrast with green plants like Rotala green, Hemianthus micranthemoides, or Hygrophila pinnatifida.

• Works well behind carpeting plants or as a mid-background color accent.

⚠️ Challenges

• Sensitive to fluctuations in CO₂ or nutrients — may cause leaf melting.

• Can lose red coloration in low light or high nitrates.

• Needs regular maintenance to prevent shading and overcrowding.

🪴 Quick Summary