Variety of Java fern

Thor's Trident java fern

Leptochilus pteropus 'Thor's Trident'

One of 7 varieties of Leptochilus pteropus · See all varieties →

Also known as Microsorum pteropus 'Thor's Trident', Java fern Thor's Trident, Microsorum pteropus var. Thor's Trident, Thor's Hammer Trident

FreshwaterBrackishRhizomeRhizome divisionPlantlets

Varieties · Leptochilus pteropus

See all 7

Care at a glance

Light
Low light
CO2
No CO₂ needed
Temperature
64–86°F
18–30°C
Max height
7.9 in
20 cm
Growth rate
Slow
Placement
Epiphyte
Type
Rhizome
pH
5.5–8.0
Hardness
0–20 dGH
Spread
5.9 in (15 cm)
Nutrient uptake
Root + water column
Growth region
Submersed or emersed
Difficulty
Easy
Family
Polypodiaceae
Origin
Cultivated selection of Southeast Asian Leptochilus pteropus

Overview

Glue or tie the rhizome to driftwood or rock and never bury it, or it will rot. It thrives in low light with no added CO2, though injected CO2 and stronger light give tighter, faster growth. It is slow and nearly bulletproof, tolerant of a wide parameter range including slightly brackish water, and it spreads by producing baby plants (plantlets) on older fronds that you can detach and reattach elsewhere.

In the wild

This is a nursery selection of Leptochilus pteropus, the java fern, which in the wild grows across Southeast Asia clinging to rocks and wood along streams and in seasonally flooded forest. Like the parent species it is an epiphytic fern that lives with its rhizome exposed, not rooted in soil. It shifts easily between submersed and emersed growth, which is how it survives fluctuating water levels in its native range.

Good to know

Microsorum pteropus belongs to the true fern family Polypodiaceae, and recent taxonomic work moves it into the genus Leptochilus, so you may see it listed as Leptochilus pteropus. 'Thor's Trident' is a hobbyist cultivar with unusually narrow leaves that fork into fine multi-pronged tips, a more delicate version of the standard 'Trident'. As a fern it reproduces by spores in nature, but the black dots on the undersides of aquarium leaves are usually sori (spore cases), not disease.

Did you know

Java fern is one of the few aquarium plants that reproduces mostly by making tiny clones of itself right on its leaf tips, so you can grow a whole colony without ever cutting the parent plant.