About the Java Fern
Species Type: Freshwater Plants
Category: Nonsubstrate Rooted
Care Level: Very Easy. Adaptable, will tolerate soft or hard water, low light, very minimal or no additional fertilization. pH 6.0 to 8.0 and GH up to 20 degrees/350ppm.
Origin: Southeast Asia; found attached to roots and rocks in streams and rivers and emersed along riverbanks and in marshes.
Java Fern's hardiness and ease of growth make it a good plant for beginning planted tank enthusiasts. It's ability to root on rock and wood means it can be grown where ordinary plants cannot. It further makes a useful plant to hide the filter tubes since it does well with a moderate current.
The plant grows leaves and roots from a stem called a rhizome; this must never be buried or it will rot. Black cotton thread may be used to initially affix the rhizome to a piece of wood or rock, and the roots will attach the plant securely. The leaves will grow between 6 and 12 inches depending upon available nutrients. Liquid fertilizer should be added to the water.
This plant assimilates nutrients from the water via the leaves and the roots; black areas on the leaves is a sign of nitrogen deficiency (ammonium and nitrate). Areas of transparency in the leaves means the plant is receiving too much light. This plant does very well under subdued and diffused light, such as a canopy of floating plants. The plant grows slowly, and older leaves that become tattered and blackened may be removed.
Once established, Java Fern reproduces by adventitious plants at the tips of leaves. The plantlets may be pulled away from the leaf when they have a few leaves and roots; if left, the leaf tip will eventually darken and the daughter plant will break away and drift until the roots are able to attach themselves to an object. The plant may also be propagated by cutting the rhizome (ensuring there are a few leaves and roots attached to each piece) and affixing it elsewhere.
This plant is very well suited for aquaria with fish that are inclined to eat plants; the bitter taste of its leaves are not relished by fish and most will not eat it. As the plant is attached to rock or wood, it is also suited to aquaria with fish that would uproot plants from the substrate. In a humid plaudarium/vivarium, Java Fern may be grown with the rhizome and roots in water and the leaves in the air; but if the air is not sufficiently moist, the leaves will dry and curl.
Several varieties have been cultivated by nurseries, and the plant also occurs with varied leaf forms in nature. One particularly-striking cultivar is M. pteropus "Windelov" (pictured in the third photo above), named in honour of Holger Windelov, the founder of the famous Danish nursery Tropica Aquarium Plants.
Microsorum pteropus was described and named by the German-Dutch botanist Carl Ludwig Blume in 1833. The genus name Microsorum--not to be spelled Microsorium--comes from the Latin and means tiny spore. The species epithet pteropus refers to the "winged base" of the leaves on the rhizome.
The family Polypodiaceae contains more than 60 genera of polypod [=having numerous feet] ferns, which today accounts for about 80% of all living fern species. A diverse group, they first appeared during the Lower Cretaceous period; the polypod radiation occurred at roughly the same time as the ascendance of angiosperms (flowering plants) and several scientists believe the two sets of diversifications may be related. Almost all are epiphytes, meaning a plant that grows non-parasitically upon another plant (such as a tree) or another object; epiphytic derives from the Greek "epi" [upon] and "phyton" [plant].
Ideal position in aquarium
Adapts for fully-submersed growth; must be affixed to objects such as bogwood or rock. Mid-ground in larger aquaria, background in small tanks. Appreciates a gentle current.
Low to moderate; in too bright a light the leaves will begin to turn transparent.
Minimum Tank Suggestion
Ideal water parameters for Java Fern
Moderately soft to hard, slightly acidic to basic (pH 6-8) water, temperature 18-30C/65-86F. Can tolerate slightly brackish conditions.