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MossAttached to hardscapeLow to medium light

Christmas moss

A moss with a distinct triangular frond structure, slower and tidier than Java moss.

Requirements

Scientific name
Vesicularia montagnei
Family
Hypnaceae
Light
Low to medium
CO₂
Beneficial
Nutrients
low
Growth rate
Slow
Placement
Attached to hardscape
Feeding
water column
Temperature
20–27 °C
pH
5.5–7.5
Hardness
1–15 °dGH

Identity

Common name
Christmas moss
Scientific name
Vesicularia montagnei
Family
Hypnaceae
Also sold as
Vesicularia vesicularis

How to plant it

The commonest way to kill an aquarium plant is to install it wrongly. This is the first thing to get right.

Tie or glue to wood or rock

Nutrition reaches this plant mainly through the water column, so liquid fertiliser matters more than substrate nutrition.

Growing conditions

InputRequirementNotes
LightLow to mediumMatch plants to the light you have rather than raising light to suit the plant — that grows algae.
CO₂BeneficialNot a requirement, though growth is faster with it.
NutrientslowDose a complete liquid fertiliser.
Temperature20–27 °C
pH5.5–7.5
Hardness1–15 °dGH
Growth rateSlow

Propagation

Divide and re-tie.

Emersed growth and melting

Commercially grown out of water. Expect the emersed leaves to die back after planting while new submersed-form leaves grow from the crown. This is a conversion, not a disease.

Common problems

  • poor frond structure in warm water
  • algae in moss

Work from the observation: melting, yellow leaves, holes in leaves and poor growth.

Fish and invertebrate compatibility

Resists grazing
good
Resists digging
excellent

Worth knowing

  • The characteristic branching structure develops best below about 25 °C.

Evidence

ClaimValueEvidence typeConfidenceSource
scientific nameVesicularia montagneiObserved / measuredhigh confidencePlants of the World Online
temperature20–27 °CAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
light requirementlow-to-mediumAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
co2 requirementbeneficialAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
growth rateslowAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
placementhardscape-attachedAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
ph5.5–7.5 pHAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis
general hardness1–15 °dGHAquarium-literature consensusmoderate confidenceAquariumHQ husbandry synthesis

Why we say this

What each figure on this page rests on, and how far that is from being independently established.

Every figure on this page has a provenance. Open any claim to see what AquariumHQ holds for it, which sources say what, and what a claim of that kind actually needs. Different claims need different evidence: an accepted scientific name is settled by one authority, while a legal restriction needs a current primary instrument. A single source is often the right answer rather than a thin one. Light and CO2 categories are aquarium conventions rather than measurements, and are labelled as such — AquariumHQ has taken no PAR readings and does not publish figures it has not taken.

scientific nameOne sourceBased on a verified authoritative source.1 citation, 1 independent origin

Checked against gbif on 2026-08-11: the catalogue name is a synonym of "Vesicularia vesicularis", which is now aliased.

What this kind of claim needs: accepted botanical name 1 authoritative source in an appropriate context. Checked against gbif on 2026-08-11. One botanical authority is what this class requires.

What would improve this: Corroborate against a second, independent source.

temperatureAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.

AquariumHQ's own position on a claim an external source could support.

What this kind of claim needs: how to grow the plant no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.

What would improve this: Go and read a source. This is reachable and has not been reached.

light requirementAquariumHQ's judgement — no authority publishes thisAquariumHQ's own position, derived from evidenced inputs.

No external authority publishes this. The rationale carries the reasoning.

What this kind of claim needs: how to grow the plant no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.

What would improve this: Keep the rationale current. There is no source to find.

co2 requirementAquariumHQ's judgement — no authority publishes thisAquariumHQ's own position, derived from evidenced inputs.

No external authority publishes this. The rationale carries the reasoning.

What this kind of claim needs: how to grow the plant no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.

What would improve this: Keep the rationale current. There is no source to find.

growth rateAquariumHQ's judgement — no authority publishes thisAquariumHQ's own position, derived from evidenced inputs.

No external authority publishes this. The rationale carries the reasoning.

What this kind of claim needs: how to grow the plant no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.

What would improve this: Keep the rationale current. There is no source to find.

placementAquariumHQ's judgement — no authority publishes thisAquariumHQ's own position, derived from evidenced inputs.

No external authority publishes this. The rationale carries the reasoning.

What this kind of claim needs: how to grow the plant no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.

What would improve this: Keep the rationale current. There is no source to find.

phAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.

AquariumHQ's own position on a claim an external source could support.

What this kind of claim needs: how to grow the plant no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.

What would improve this: Go and read a source. This is reachable and has not been reached.

general hardnessAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.

AquariumHQ's own position on a claim an external source could support.

What this kind of claim needs: how to grow the plant no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.

What would improve this: Go and read a source. This is reachable and has not been reached.