The Microsorium pteropus or Java fern by its popular name, is a well known and popular flora among aquascapers. It is easily available and widely distributed worldwide.
In the wild, the Java fern is found in streams and rivers. They are either fully submerged, or partially, with the spray of water constantly wetting the leaves. In an aquascape, the Java fern should not be planted in the substrate, but be attached to rocks or wood, as how it is in the wild. Its roots enables it to grab onto these surfaces and anchor the fern in its place, which prevents it from drifting with the current.
Many new aquascapers use the Java fern as part of the first aquascape because of its hardy properties. Unlike many other aquatic flora, the Java fern is not terribly particular about lighting levels and they have been known to survive in aquariums with just ambience lighting. The leaves of the fern almost makes up the entire flora, and this helps in maximizing the amount of light received.
The Java fern is also not too concerned about CO2 or nutrient levels. The reason why it needs so little light is also the reason why it requires no extra CO2 and little nutrients, and that is because it’s slow growing. CO2 that is already present in the aquarium through gaseous exchange at the water’s surface will be sufficient and any nutrients that is leaked from fish food or fish waste will feed the fern.
Although good lighting, injected CO2 and additional nutrients are not needed for the well-being of the Java fern, we have kept it under these conditions. The only difference we noticed was that the leaves were noticeably a brighter green in colour, sometimes with a almost translucent quality to it. Some aquarists have referred to this as a ‘burn out’, but we did not notice any difference in its health, only in its appearance. In our resident 30 litre tank, we will be using the Java fern pretty extensively in such a condition, we will keep you updated with its progress.
The Java fern grows to a maximum height of about 25cm and should be kept at temperatures of about 18 to 28 degrees Celsius. If you have fauna that are herbivorous, you may want to try the Java fern as it contains chemicals that deters such fauna.
Dead leaves of the Java fern will turn black and these should be manually removed. However, you spot a broken leaf, it can be left alone and need not be removed if you don’t want to. Propagation of the Java fern is by the growing of ‘daughter’ plantlets at the edges of the leaves.