Hemianthus callitrichoides 'Cuba,' commonly known as Dwarf Baby Tears or simply HC, is a popular and highly sought-after aquatic plant in the aquarium hobby. Known for its delicate, tiny leaves and its ability to form dense, lush carpets, it is often used in aquascaping to create stunning foregrounds and add a sense of scale to aquarium landscapes.

Characteristics

• Appearance: Hemianthus callitrichoides 'Cuba' has very small, round, bright green leaves. The plant's fine texture and compact growth make it ideal for creating a vibrant green carpet across the substrate.
• Size: It grows very low to the ground, usually reaching a height of about 1-3 cm (0.4-1.2 inches). The individual leaves are typically less than 1 mm in size.

Care Requirements

• Light: High-intensity lighting is necessary for optimal growth. Hemianthus callitrichoides 'Cuba' requires bright, consistent light to thrive and maintain its compact form. Insufficient lighting can cause the plant to grow leggy and lose its dense carpet appearance.
• CO2: Supplemental CO2 injection is highly recommended to achieve the best growth and maintain the plant's health. CO2 helps the plant photosynthesize more efficiently, promoting robust growth and vibrant coloration.
• Substrate: A nutrient-rich substrate is beneficial for Hemianthus callitrichoides 'Cuba'. Fine-grained substrates, such as aqua soil, provide a good anchoring medium and support healthy root development.
• Water Parameters:
  • Temperature: 68-78°F (20-26°C)
  • pH: 5.0-7.5
  • Hardness: Soft to moderately hard water (1-12 dGH)

Growth and Maintenance

• Growth Rate: Hemianthus callitrichoides 'Cuba' has a moderate to fast growth rate under optimal conditions. Regular trimming is necessary to maintain its carpet form and prevent it from growing too tall.
• Propagation: The plant propagates by sending out runners that develop into new plantlets. These can be separated and replanted to expand the carpet or fill in bare areas.

Aquascaping Uses

• Foreground Plant: Due to its low-growing nature and fine texture, HC 'Cuba' is ideal for creating lush, green carpets in the foreground of aquariums.
• Nano Tanks: Its small size makes it perfect for use in nano aquariums, where it can create a sense of scale and enhance the overall aesthetic.
• Contrast and Detail: It adds a fine-textured contrast to larger-leaved plants and hardscape elements, bringing detail and a natural look to aquascapes.

Challenges

• High Maintenance: Maintaining Hemianthus callitrichoides 'Cuba' can be challenging due to its high light and CO2 requirements. It is more suitable for experienced aquarists.
• Algae Growth: High light and nutrient-rich environments can also promote algae growth, which can overtake the HC 'Cuba' if not managed properly. Regular maintenance, including trimming and cleaning, is essential.

Benefits

• Aesthetic Appeal: Provides a stunning, vibrant green carpet that enhances the visual appeal of aquariums.
• Habitat: Offers shelter and grazing surfaces for small fish and invertebrates, contributing to a more dynamic and interactive environment.

Overall, Hemianthus callitrichoides 'Cuba' is a beautiful and rewarding plant for aquascapers willing to meet its care requirements. With proper maintenance, it can create breathtaking aquascapes and serve as a focal point in any planted aquarium.