Java fern
Leptochilus pteropus
Also known asMicrosorum pteropus (synonym) · Java fern
Water parameters
Light and nutrients
Substrate type: epiphyte. Propagation: rhizome division.
Substrate compatibility
| Substrate | pH effect | Nutrient load |
|---|---|---|
| Wood and rock mounts (Hardscape mount) | varies | none |
| Inert sand (Pool filter sand) | neutral / inert | none |
| Inert gravel (Aquarium gravel) | neutral / inert | none |
| Limestone gravel (Crushed coral) | raises pH | none |
| Bare bottom (no substrate) (Bare bottom) | n/a | none |
| Aquasoil (ADA Amazonia) | lowers pH | very high |
| Mineralized clay substrate (Seachem Fluorite) | neutral / inert | moderate |
With fish
Origin and habitat
One of the best-known aquarium plants in the world, Java fern, the aquatic fern long called Microsorum pteropus and now reclassified as Leptochilus pteropus, family Polypodiaceae. It is native across tropical and subtropical Asia, recorded from northeastern India through Malaysia, Thailand and southern China and the wider region, growing attached to rocks and wood in and beside streams. Leathery, dark-green fronds rise from a creeping rhizome, 15–30 cm in the standard form. Many cultivars are sold, among them 'Narrow Leaf', the forked-tipped 'Windelov', the finger-lobed 'Trident', the broad hammered 'Philippine' and various dwarf forms. It is a low-tech staple, taking low light, no CO2 and a wide range of water, and its tough leaves are unpalatable to most plant-eating fish.
Outdoor pond use
- USDA zones
- 8–13 (winter low around -12°C or warmer)
Care notes
Among the easiest of all aquarium plants. Attach the rhizome to driftwood or rock with glue, thread or line, and never bury it, since a buried rhizome rots and the plant dies, just as with Anubias; the roots grip the hardscape over time. Low to moderate light suits it; under strong light, especially without CO2, the slow leaves collect algae such as black beard and green spot, so keep light moderate. Growth is slow, a new frond every week or two, and CO2 makes little difference compared with its effect on stem plants. It tolerates pH from around 5.5 to 8, soft to hard water, a wide temperature range and even low-end brackish conditions. It spreads by dividing the rhizome and by plantlets that sprout right off mature fronds, growing their own roots before dropping away; collect and reattach them. Brown or black spots on the leaves are usually normal spore patches or young plantlets, not disease, though sometimes they signal nutrient issues. Trim old, damaged or algae-covered fronds at the base. Its toughness, looks and fish-resistance make it the default beginner plant. It is an ornamental epiphyte, not a crop, so it is unsuited to media-bed aquaponics or hydroponics.