Dennerle Hemianthus Callitrichoides 'Cuba'

Hemianthus callitrichoides 'Cuba', commonly known as HC Cuba or Dwarf Baby Tears, is universally recognized as the smallest aquarium plant available and a hallmark foreground species of the high-end planted aquarium hobby. Native to Cuba (discovered near Havana), it features minute, rounded leaves arranged alternately along delicate trailing stems, forming an extraordinarily fine-textured, vivid green carpet when established.

An HC Cuba carpet is one of the most sought-after effects in aquascaping, creating a perfect grass-like lawn that photographs beautifully and enhances the visual depth of any aquascape. Under strong light and CO2 injection, the plant pearls (releases oxygen bubbles) throughout the day, creating a glittering visual effect that epitomizes the nature aquarium aesthetic.

However, HC Cuba is demanding: it requires high light (50+ PAR at substrate level), consistent CO2 injection, nutrient-rich aqua soil substrate, and stable water parameters. Without these, it typically melts rather than carpeting. Proper setup preparation (choosing the right substrate, ensuring CO2 is running before planting) is critical to success.

Dennerle produces this as a tissue culture (in vitro), providing a clean, contaminant-free product ideal for establishing new aquascapes.

Light: Very high light required (50–100+ PAR at substrate level). The carpet will fail without sufficient intensity.

CO2: CO2 injection is mandatory (20–30 mg/L). Cannot be reliably carpeted without CO2.

Substrate: Rich aqua soil (ADA Amazonia, Tropica Soil, Dennerle Scaper's Soil) is essential. HC Cuba needs nutrient-rich substrate to anchor and spread.

Planting: Plant small clumps (1 cm diameter) spaced 1–2 cm apart across the foreground. Takes 4–8 weeks to carpet under ideal conditions. Patience is required.

Water Parameters: pH 5.5–7.0, temperature 20–28°C, soft water (GH 2–10). Soft, slightly acidic water is strongly preferred.

Maintenance: Trim regularly to maintain carpet height of 1–2 cm. Allow light penetration to base to prevent dieback. A demanding plant — success requires full setup preparation.