Introduction & Summary
Java fern, or Microsorum pteropus as it is known in the scientific community, is and aquatic fern that, just like the name suggests, originates from the waters of Java. It is a very hardy plant that can adapt to most water conditions including brackish water. Add to this that the Java fern tolerates low light conditions and can grow stuck to any surface, and it becomes easy to see why this is such a popular aquarium plant.
Many fish species like to hide among or even spawn on java fern. It is also one of the few plants that can be kept with most plant eating fish and digging cichlids; it is really hardy and have leaves that most fish species will not eat.
The java fern is said to be slow growing but can still grow impressively big in a year or two. Large plants can be divided to create new plants. It is also possible cut single leaves of a plant to start new plants.
Java fern is available in most aquarium stores and in several varieties. If you can not find the variety you want in your local fish store you should be able to find online and have it shipped to you. Java fern tolerates shipping well as long as it is provided with moisture and it is not too cold.
Regular Java fern
The regular or classic java fern is the type that was introduced into the hobby first and the type you can find in the wild in Java. It has narrow long leaves with a dark green color. This is the most commonly sold type of java fern and the type all other types originate from. It is a beautiful plant that can be used to great affect in aquariums and it is usually cheaper to buy than the other types. It is also easier to find another fish keeper that might be willing to sell or even give you a few plants of this type if you do not want to pay pet store prices.
Windelof Java fern
The Windelof Java fern sports branched leaf tops making it look like a forest at the top of each leaf. This makes this type a lot more fine leafed than the regular java fern. It is often a bit more expensive than regular java fern, but well worth its cost due to its unique look and the fact that it offers an excellent hiding space for small fish. Windelof Java fern first occurred in the Tropica plant farm population. Tropica is a large Danish plant grower that provides plants to aquarium stores around the world, and they have registered and protected this type of java fern. It is named after Tropica's founder Holger Windeløv The Windelof Java fern is as hardy and easy to care for as the basic type; it does however require a bit more light to grow optimally.
Staghorn Java Fern
The staghorn java fern looks a lot like the Windelof Java fern and it is possible that this is a name used to sell the same mutation as seen in the Windelof Java fern without violating Tropica's rights to the Windelof Java fern name. The Staghorn java fern is just like most other types of this plant hardy and will adapt to most water and lighting conditions.
Tropica Java Fern
The Tropica Java fern is another type pf java fern that has been developed by Tropica. It looks a little bit different than classic java fern; the leaves are broader and this plant grows bigger than the classic type. It is easily told a part from regular java fern due to the leaves and their narration. It is a hardy plant with the same requirements as the type found in nature.
Other more uncommon types of java fern include:
Red Java Fern
Once sold by Tropica but removed from the market in 2007 since the color only showed in plants where the leaves where allowed to reach above the water surface.
Narrow leaf Java Fern
This is, as the name suggests, a type of fern with more narrow leaves than the classic java fern. Besides this difference, it is basically the same fern as the regular type and will require the same care as most other types of java fern.
Split narrow leaf java fern
A rare type of java fern where the end of the narrow leaf splits in two. It is a hardy plant with a very unusual look and can be used to great effect in planted aquariums.
Philippine Java Fern
The Philippine java fern has wide and twisted soft green leafs. It is a great solitaire that will work excellent as a focal point in the aquarium.
Using Java Fern
Java fern has a lot of usages in aquariums and it is up to you to decide how you want to use java fern, if all, in your aquarium. Below I will list some common usages for the plant.
One of the most common ways to use the plant is to plant it where other plants would simply not grow such as on roots and rocks but also on things like PVC pipes and aquarium equipment. This is an excellent way to hide equipment and other unsightly things in the aquarium. The fact that it grows on any surface also makes it possible to have a rosette plant growing on a substrate closer to the surface of the aquarium which can look very good if done correctly. It is also possible to cover an entire side of the tank with java fern from top to bottom.
Most fish that eat plants such as Mbuna cichlids do not like java fern which makes it ideal for many aquariums where other plants can't survive. It is also hardy enough not to mind being kept in aquariums with species that like to dig and move things around, e.g. large cichlids. All in all, this makes java ferns ideal in many tanks where other species of plants can't be kept. You should however know that some species of fish, such as clown plecos, uaru and pacu, will eat java fern.
Java fern can survive and even thrive in tanks where the water conditions do not allow for other fern types to be kept, such as tanks with very hard water or brackish water tanks. Java fern will do well in most conditions and is therefore a recommended choice when nothing else wants to grow.
Edit: I have received the question if java fern can be used in saltwater aquariums. The simple answer is no, although it depends on salinity. Different strains and even individual plants have different tolerance for salinity and the speed in which the plant introduced to higher salinity will also affect how well it tolerates the salinity.
Java fern will usually not tolerate pure sea water. I have seen a few cases where plants survive, but do not grow larger, in saltwater. I have been told about but not seen specimens that are said to live and grow slowly in a marine environment. This is however to be considered exceptions and not the norm.
Planting Java Fern
Java fern can be planted in the substrate but will usually not root and will do better if tied or otherwise secured to a root, rock or other object. Before planting - or rather securing - the plant you should cut away damaged parts and parts covered in algae. If the entire plant is covered in algae you can trim it aggressively without cutting into the root stem. You can also trim the roots a bit if there are a lot of them.
Tie the plant into the position you want it in. This can be done using nylon fishing line, or for the lazy, by using a rubber band. After a month or two the plant will have secured itself to the substrate and the line or band is no longer needed.
Java Fern Care
Java ferns are very hardy plants that need next to no care at all. They do well in low light conditions so it is not a problem if they are shaded by another plant. Being slow growing, they seldom need pruning. It can however be good to remove damaged leaves and, if needed, algae infested leaves.
When a java fern has grown too big and needs to be pruned down you can cut it almost however you see fit as long as you keep at least a part of the root stem.
Java fern only very seldom need added nutrition. You can find more info on fertilization further down on this page.
Java fern light requirements
All types of java fern have low light requirements, although some types like the Windelof java fern prefers a bit more light than the rest. The Red java fern requires a lot more light to develop the red color and will only turn red when grown in emergent conditions (i.e. when it can reach above the surface of the water).
Too much light is a bigger problem than little light for java ferns. They do however usually do well in well lit aquariums and will grow quicker under these conditions. Java fern is generally considered a slow growing plant, but can grow very quick in well lit environments.
If your java fern seems to dislike the very strong light, it is recommended that you try to shade the plant. This is however not an issue in most, not to say all, everyday aquariums - only in well lit aquariums set up to house especially light demanding plants. It can also be a problem if you use a lighting setup designed for reef coral aquariums.
Most everyday aquarists do not need to take lighting into consideration when getting a java fern, as long as the plants are to be kept in a lit aquarium.
Java fern & Nutrition
Java fern takes all its nutrients directly out of the water and any fertilization therefore needs to be dissolved in the water. Nutrient tablets do not work well, although they will have some affect if stuck under the plants.
Added nutrition is usually not needed as java ferns will find enough nutrients in the water anyway. However, if you have other plants that require a higher amount of nutrients in the water this will not be a problem either. Stronger lighting and more nutrients will cause the java ferns to grow quicker.
If you want your java fern to grow at optimal rate you should provide them with nutrients, enough light and extra carbon-dioxide in the water. Adding carbon-dioxide to the water will have a positive effect on other plants as well.
Propagating Java Ferns
Propagating java fern is easy and can be done 3 distinct ways:
Split existing plants. Large plants can be cut into several plants to create new plants.
Use baby plants. Baby plants are formed on the leaves of the existing plant. Wait until these baby plants have some roots and 2-3 leaves.
Leaf cutting. Cut off a leaf and let it float around in the tank until it develops baby plants as described in 2. This method can be used to force a leaf to create a baby plant if the entire plant doesn't want to.
In the wild, java fern also propagate through the use of spores (just like all other ferns). This method is however very difficult and unpractical to use in aquariums. You can read more about how to propagate java fern on this page.