Fissidens Fontanus (Fissidens fontanus) Care Guide
A striking aquatic moss with tiny feathery fronds arranged in a flat fan-like pattern resembling miniature palm trees.
Compiled by Aquairi from published sources · Published · Updated
Overview
Fissidens fontanus is an aquatic plant in the family Fissidentaceae. A striking aquatic moss with tiny feathery fronds arranged in a flat fan-like pattern resembling miniature palm trees. Grows very slowly but forms incredibly dense and detailed textures on rocks and driftwood, prized in aquascaping contests.
Taxonomy
- Family: Fissidentaceae
- Genus: Fissidens
- Scientific name: Fissidens fontanus
- Other names: Phoenix Moss, Palm Moss
Habitat
A small aquatic moss native to the eastern half of North America, also found in scattered localities across Europe and Asia. Grows on submerged rocks, tree roots and wood in streams; the flat fan-shaped fronds resemble miniature palm leaves, hence the common name Phoenix Moss.
Growth requirements
- Light: low (≈30-50 PAR at substrate)
- CO2: optional (CO2 improves growth and coloration)
- Temperature: 18-26 °C
- pH: 6-7.5
- GH: 2-12 °dGH
- Substrate: not applicable (attached to wood or stone)
- Nutrient demand: low
- Growth rate: slow
- Difficulty: intermediate
Placement
- Recommended placement: epiphyte (attached to wood or stone)
- Maximum height: 5 cm
- Trim every: 30 days
Propagation
In cultivation the plant is propagated by vegetative division or fragmentation.
Propagating Fissidens fontanus (Phoenix Moss)
Overview
Fissidens fontanus, often called Phoenix moss or limp pocket moss, is an aquatic moss with lance-like leaves around 2-7 mm long, each carrying a small folded lobe that resembles a pocket. The leaves sit in an alternating pattern, giving the dense, feathery, palm-like texture that makes this moss prized in aquascaping. It forms thick mats over flat bedrock, cobbles, root masses and logs, anchoring directly to these surfaces.
It grows in slow-moving or still water and tolerates a pH range of roughly 6.0 to 8.0. Importantly, it is intolerant to desiccation and dries out quickly if left out of water, so keep cuttings submerged or in high humidity at all times.
Propagation Method (Division)
Because it is a moss, Fissidens fontanus is propagated by division rather than by stem cuttings. You simply separate a portion of the existing mat and re-attach it to new hardscape, where it will gradually knit itself down and form a fresh mat of its own.
Step-by-Step
- Pull a healthy section of the moss mat from the parent surface, keeping it wet the whole time.
- Tease it into a thin, even layer rather than a thick clump; thin layers attach and grow far better.
- Spread the layer over clean wood or rock and secure it with cotton thread, fishing line or a fine mesh.
- Place the piece in slow-moving or still water within the accepted pH range.
- Leave it undisturbed for several weeks so it can anchor before you remove any temporary thread.
Conditions for Healthy Growth
- Water: slow-moving or still, pH approximately 6.0 to 8.0.
- Light: low to moderate is sufficient; intense light is not required.
- Surface: flat bedrock, cobbles, driftwood or root masses, which it anchors to naturally.
- Always submerged: it cannot tolerate drying out.
Maintenance
Growth is very slow, so trimming is infrequent. Light grooming keeps the mat dense and tidy, and the trimmings you remove can be tied onto new hardscape as fresh divisions. Gentle flow helps keep detritus from settling into the fine fronds.
Common Challenges
- Slow attachment: thick clumps and strong current slow anchoring; keep layers thin and flow gentle.
- Drying out: any exposure to air during planting can damage the moss permanently.
- Detritus trapping: fine fronds catch debris, so maintain clean water and light flow.