Riccia fluitans

🌿 Riccia fluitans

Riccia fluitans, commonly known as Crystalwort or Riccia Moss, is a world-renowned floating liverwort made famous in aquascaping by Takashi Amano. Celebrated for its bright emerald-green color and fork-branched thallus structure, it is capable of forming dense floating mats or carpeted mounds submerged under high-tech conditions.

🌱 Growth & Appearance

This species consists of intricate, Y-shaped branches that interlock to build thick, delicate cushions. Naturally floating, it does not produce true roots or rhizoids to anchor itself to surfaces.

Under strong lighting and CO₂ supplementation, Riccia exhibits an extraordinary tendency to pearl, trapping tiny oxygen bubbles across its green tips that glisten like crystals throughout the day.

💡 Lighting & CO₂

Riccia fluitans can grow as a simple floating plant under low to moderate lighting without added carbon dioxide. However, to anchor it underwater as a lush carpet or hardscape accent, high lighting and pressurized CO₂ injection are essential.

Providing high light and stable CO₂ prevents the inner base of submerged mats from dying off while keeping growth compact, intensely green, and pearling continuously.

🪴 Planting & Maintenance

To grow Riccia submerged, tie thin layers onto flat rocks, stainless steel mesh pads, or driftwood using hairnet or fine monofilament line. As it grows, fresh branches will push through the mesh to form a seamless, rounded cushion.

Because it lacks roots and remains naturally buoyant, regular trimming is required. Trim the cushion short before the mound grows too thick; otherwise, the lower shaded layers will rot and cause the entire mat to detach and float to the surface.

🌿 Best Use

Riccia fluitans is a striking foreground carpet or hardscape accent in high-tech nature aquascapes, Japanese-style layouts, and shrimp setups.

Its bright lime-green tone and shimmering pearling effect provide incredible contrast when placed alongside dark lava rocks, driftwood bases, or dark red stem plants.

✨ Plant Profile

Difficulty: Moderate (Submerged) / Easy (Floating)

Growth Rate: Fast

Lighting: Medium to High

CO₂: Required (for Submerged Carpeting) / Optional (Floating)

Temperature: 15–28°C

Placement: Foreground (Tied) or Surface (Floating)

Growth Type: Liverwort / Floating

Propagation: Division / Frond Fragments