Microsorum pteropus (Java Fern): hardy plant to attach for a low-tech aquarium
An amphibious plant with resilient foliage
Microsorum pteropus, known as Java Fern, is a true amphibious fern: in nature, it extends from the bank to the bottom. Its dark green, leathery, decorative foliage is particularly resistant to herbivorous fish. It is a slow-growing, highly tolerant plant, ideal for a natural or low-tech aquarium.
A botanical note: the brown-orange spots visible on the underside of some leaves are sporangia (which produce spores in ferns). They have nothing to do with a disease.
Why choose Java Fern?
- Attach it to a root or stone: no substrate required.
- Low-tech: grows without CO₂, in simple conditions and without fertilizer.
- Hardy and highly tolerant: soft water, hard water, or even slightly brackish water, or even... without water in a paludarium!
- Leathery leaves: excellent durability with nibbling fish (goldfish).
- Long-lasting midground or background decoration; its sumptuous dark green highlights lighter plants.
- Easy propagation: by dividing the rhizome, but especially by removing the young plantlets that form at the tips of the leaves.
Planting and care advice
- Never bury the rhizome (risk of rot).
- Attach the plant to a root or stone (fishing line, soft tie, or by wedging it between two stones, for example).
- Light: low to medium. Perfect for planting in a less brightly lit area.
- Flow: moderate current. Avoid directing too strong a current at the fronds.
- Maintenance: remove very old and browning leaves. Divide the rhizome from time to time. Replant the baby ferns growing at the tips of the leaves.
- Temperature: tropical plant (optimal range of 20 to 28 °C). Intended for aquariums or paludariums (does not tolerate cold outdoors).
Possible uses
- Low-tech aquarium: a structural plant requiring no technical substrate, CO₂, or fertilizer.
- Aquascaping: natural covering for roots and rocks, use of shaded areas, dark green background to play with shades.
- Paludarium / open tank: can grow emersed in a humid area, allowing for superb displays.
- Killifish aquariums: its low light requirement makes it suitable for tanks housing species that appreciate dim conditions.
FAQ – Microsorum pteropus / Java Fern
How should it be attached correctly?
Place the rhizome against a root or stone and attach it (with fishing line or a soft tie). It will then attach itself.
Does it need CO₂?
No. It grows without CO₂ in a balanced tank. Its slow growth requires neither CO₂ nor fertilizer.
Is it suitable for beginners?
Yes, it is one of the most tolerant plants for starting your first aquarium.
Can I place it on the substrate?
Yes, as long as the rhizome remains unburied. Never bury it; it is better to attach it to a decorative element.
How fast does it grow?
Rather slowly. Rely on rhizome division, and even more on the plantlets formed at the tips of the leaves, to propagate it.
Additional information
- Scientific name: Microsorum pteropus
- Plant type: slow-growing aquatic fern
- Light: preferably moderate, or even low.
- Ideal temperature: 20 to 28°C, minimum 16°C.
- Size: can reach 40 cm for the largest mature specimens under the best conditions.
- Pack size: 6 plants (indicative weight: 10 g).
- Guarantee: without rock wool or any artificial substrate of any kind.
- Recommendation: as a precaution, please never release this plant into the wild. It is not native to our regions and should not normally become naturalized, but we must protect our ecosystems.
