Hemianthus callitrichoides ‘Cuba’ (HC Cuba) is a tiny foreground carpet from west of Havana. The millimetre-sized, bright-green rounded leaves sit tight on creeping stems and form a very fine lawn — one of the smallest carpeting plants in the hobby.
It suits high-tech planted tanks and Iwagumi layouts. With strong light and stable CO2 it can pearl — small oxygen bubbles collecting under the leaves.
Key features
- Very small leaves that read well in nano tanks and detailed hardscape
- Pearls readily in a high-tech setup
- Weaves a tight mat that follows the substrate and stone edges
Water and system compatibility
Freshwater aquariums only. Not for marine or reef systems. Needs a high-tech planted tank: strong light, pressurised CO2, and regular fertiliser.
Specifications
- Type: carpeting / micro-stem
- Origin: Cuba
- Growth rate: moderate to fast in high-tech conditions
- Height: 0.5–3 cm
- Light: high
- CO2: required — pressurised injection is needed for it to carpet
- Placement: foreground
Directions
How to plant
- Tissue culture: rinse the gel off under cool water. Cut the mass into pencil-eraser-sized portions with sharp scissors.
- Potted: strip the rockwool carefully so the fine roots do not snap.
- Plant each cluster deep in fine-grain powder aquasoil with fine tweezers, 1–2 cm apart. Leave only a few leaves showing. Coarse gravel will not hold the roots — use powder soil.
Light, CO2, and nutrients
Strong, full-spectrum light keeps it creeping flat. It also needs steady pressurised CO2 and regular liquid fertiliser (including iron and potassium). Without these it yellows, melts, or lifts and floats.
Trimming
Once the carpet fills in, mow it with sharp curved scissors to about 1 cm thick. If it layers too deep, the bottom dies from lack of light and the lawn can lift off and float.
Water parameters
- Temperature: 20°C–26°C
- pH: 5.0–7.5
- Hardness: soft to medium (4–12 dGH)
