The Alien Sea Urchin: Eriocaulon Cinereum
A unique rosette plant that looks like a metallic sea urchin. Known for being demanding and sensitive to water hardness.

The Alien Sea Urchin
Eriocaulon cinereum, commonly known as the Alien Sea Urchin, is a captivating aquatic plant revered for its unique, structural appearance. This species features slender, elongated stems topped with spherical clusters of tiny white or pale green flowers, resembling the spiky texture of an urchin. Eriocaulon cinereum serves as a focal point in aquascapes, lending both height and architectural complexity. Its elegant form sways gracefully in the water, enhancing the natural beauty of any underwater landscape.
Care Guide
Maintaining Eriocaulon cinereum requires attention to several specific conditions to ensure its optimal growth.
- Lighting: Provide moderate to high light (around 100-200 PAR). A light spectrum of 6,500K is ideal to promote healthy growth and vibrant coloration.
- Water Parameters: Aim for a temperature range of 22-28°C (72-82°F), with a pH level between 6.5 and 7.5. Soft to moderately hard water is best for this plant.
- Trimming: Regular trimming is recommended to prevent overcrowding and to stimulate new growth. Inspect the plant weekly, removing any dead or decaying leaves.
Nutrient Requirements
Light
Eriocaulon cinereum thrives under bright lighting conditions. Ensure the plant receives adequate illumination for at least 10-12 hours per day to promote robust growth.
CO2
Supplementing with CO2 is beneficial for enhancing the growth rate and overall health of the plant. A range of 20-30 mg/L of CO2 is ideal for achieving lush foliage.
Fertilization
Utilize a comprehensive liquid fertilizer or nutrient-rich substrate to provide essential macro and micronutrients. Regular fertilization ensures that Eriocaulon cinereum obtains balanced nutrition and maintains its aesthetic form.
Natural Biomes
Eriocaulon cinereum is native to diverse freshwater habitats. It can be found in the following biomes:
These biomes are characterized by their rich biodiversity and nutrient-dense waters that support the growth of a variety of aquatic plants.
Livestock Compatibility
Eriocaulon cinereum coexists harmoniously with various species of fish and shrimp. Ideal tank mates include:
- Shrimp: Cherry shrimp and Amano shrimp thrive among the plant’s structure, benefiting from the cover it provides.
- Fish: Small and peaceful fish species such as Neocaridina shrimp, Rasboras, and Tetra varieties are excellent companions. They won’t disturb the delicate foliage while enhancing the overall visual appeal of the aquascape.
Integrating Eriocaulon cinereum into your aquarium will not only enhance the aesthetic appeal but will also create a conducive environment for a thriving aquatic community.