| Characteristics | Details |
|---|---|
| Genus | Myriophyllum |
| Species | Myriophyllum sp. ‘Guyana’ |
| Family | Haloragaceae |
| Origin | South America (likely French Guiana) |
| Common Name | Guyana Milfoil |
| Lighting Requirements | Medium to high (±80–150 µmol m⁻² s⁻¹ PAR) |
| Optimal Temperature | 22–28°C |
| Growth Rate | Moderate |
| Placement | Midground to background |
| Plant Height | 5–30 cm |
| Ideal pH | 6.0–7.5 |
| Water Hardness | GH 3–10 dGH; KH 1–6 dKH |
| CO₂ Requirement | Medium |
| Propagation | Stem cuttings (topping and replanting the upper portion) |
Additional Information
Myriophyllum sp. ‘Guyana’ is a stem aquarium plant that grows in dense clusters with fine leaves forming tightly packed branching structures. It maintains a consistently bright green coloration, even under high lighting conditions. Individual stems are relatively short, typically reaching only about 2–3 cm in length before branching, but they grow rapidly and form dense, bushy clumps. This makes the plant particularly useful for increasing density in the midground to background, while providing visual contrast against darker or broad-leaved species.
The plant is believed to originate from the Guyana region, although precise distribution data remains limited. It first appeared in the aquarium trade around 2011 and is known for its more compact size compared to other Myriophyllum species.
Requirements and Care
Growth Characteristics
Myriophyllum sp. ‘Guyana’ exhibits a vertical branching growth pattern, making it ideal for creating texture and depth in aquascapes. Under favorable conditions, it grows steadily and develops into dense, bushy formations. Adequate lighting is critical, as low light conditions can result in thinner growth with elongated internodes. In contrast, stronger lighting combined with sufficient CO₂ promotes faster growth and increased branching, producing a fuller and more textured appearance.
Lighting
Lighting requirements fall within the medium to high range (±80–150 µmol m⁻² s⁻¹ PAR). The plant can grow well under moderate lighting, but higher intensity significantly improves branching density and growth speed. Aquascapes with stronger lighting systems will typically observe faster development and more compact structures, while low light reduces overall performance and density.
CO₂ and Carbon
Like most aquarium plants, Myriophyllum sp. ‘Guyana’ performs best with CO₂ supplementation. A moderate level of CO₂ injection supports healthy growth and reduces stress associated with carbon limitation. While the plant can survive in non-CO₂ systems, its density and overall performance will decline. For optimal results, a stable and controlled CO₂ system is strongly recommended.
Nutrients
Balanced nutrient availability is essential for maintaining plant health. This species requires sufficient macronutrients and micronutrients, particularly nitrogen, phosphorus, and potassium. Regular fertilization supports consistent growth and helps maintain its bright green coloration. In systems with CO₂ injection, liquid fertilization can further optimize performance.
Water Parameters
The plant adapts well to a range of water conditions but performs best under stable parameters. The ideal temperature range is 22–28°C, with a pH between 6.0 and 7.5. Water hardness can vary from 3–10 dGH and 1–6 dKH. Stability is critical, as significant fluctuations may induce stress and increase the risk of algae issues.
Substrate
Myriophyllum sp. ‘Guyana’ is not highly demanding in terms of substrate, but a nutrient-rich substrate will enhance growth and overall health. Aquasoil or other nutrient-dense substrates are recommended to support root development and provide a stable growth environment.
Propagation
Propagation is relatively simple and is typically done by cutting the top portion of the plant (approximately 3–4 inches) and replanting it. Older lower stems tend to lose leaves and are more prone to algae, so regular trimming is necessary. After several trimming cycles, it is advisable to remove older stems entirely and replant fresh, healthy tops to maintain plant quality.
Conclusion
Myriophyllum sp. ‘Guyana’ is an excellent choice for aquascapes requiring a bright green plant with a dense, bushy growth form. It is suitable for both low-tech and high-tech systems, provided that appropriate lighting, CO₂, and nutrient conditions are maintained. Although slightly more delicate compared to other Myriophyllum species, it is particularly well-suited for smaller aquascapes or nano tanks. With proper care, it can deliver strong aesthetic value through its lush, vibrant green appearance and compact structure.
