Riccardia spp.

Species description

Care, breeding and tankmates

Plant profile

Placement

Midground

These liverworts are obligate epiphytes and must be secured to rocks, wood, or mesh pads. They are typically used in the foreground or as accent plants on midground hardscape structures. Never cover them with soil or sand, as they require direct exposure to water flow and light.

Botanical form

epiphyte or epilith

The generic Riccardia botanical form features a creeping, extensively branched thallus that looks like miniature, dark green coral. They lack true roots, stems, or leaves, relying on tiny rhizoids to grip surfaces tightly. The dense mats they form provide a unique, highly textured surface.

Growth

Slow

They are notoriously slow growers, requiring stable conditions and time to form dense cushions. CO2 injection is highly recommended to encourage steady growth and maintain their compact form. Under low tech conditions, their growth is almost imperceptible.

Substrate

None

Plants within the Riccardia genus are predominantly epiphytic liverworts that do not possess roots and do not need a substrate for cultivation. These versatile plants naturally grow by creeping along and anchoring onto solid surfaces like driftwood, lava rock, or specialized planting meshes. Nutrient absorption occurs entirely through the surface of their cellular structure directly from the surrounding water. They should be affixed to a hardscape anchor point where they will eventually develop a strong hold and form dense, textured green mats.

Column fertilization

Recommended

Since they draw nutrition directly from the water, a balanced liquid fertilizer is essential. Dosing should be lean but consistent to ensure the plants have a steady supply of trace elements and iron. This keeps their coloration dark and vibrant.

Root fertilization

None

Root fertilization is completely ineffective and unnecessary. Because they are grown on hardscape, they have no interaction with the substrate. All nutritional management must be handled via the water column.

Trimming

Occasional

When the mats become excessively thick, the lower portions receive no light and can die, causing the whole clump to detach. Regular thinning with scissors is vital to maintain their grip on the hardscape. The trimmings should be siphoned out or reused.

Propagation

Cuttings

Propagation is straightforward through fragmentation. Any piece of the thallus that is removed and reattached to a solid surface will continue to grow. Cyanoacrylate super glue is the most common and effective method for attaching fragments.

Sensitivity

Moderate

They are highly sensitive to algae infestations, particularly thread and brush algae, which are very difficult to remove without damaging the plant. They prefer excellent water circulation to keep their surfaces clean. They also favor cooler water and may struggle in tanks kept above 28°C.

Layout role

Epiphyte, Nano

Riccardia species are the ultimate detail plants in aquascaping, used to add age and realism to the hardscape. They create beautiful, moss-like accents that contrast nicely with broader-leafed epiphytes like Anubias. Their compact nature makes them highly favored for intricate Iwagumi or diorama layouts.