Java Fern is undoubtedly one of the most famous aquatic plants. Many aquarium enthusiasts keep Java Fern in their tanks for decoration purposes and because of its characteristics.
Their lush green coloration keeps the lively vibe in the tank, that’s one. On top of that, they can grow pretty tall. Up to 13.5 inches, to be precise. With their possible growth size, you can expect a mini jungle background for your tank inhabitants.
Two, they are relatively sturdy and don’t require much of your attention. In fact, it’s nearly impossible to kill the plant unless you actually try hard to prove its strength. The Java Fern doesn’t demand strict water parameters. They can even survive in both fresh and brackish water!
With those qualities, we can agree that Java Fern is one of the easiest plants to keep, even if you are a total beginner. They are beautiful, easy to care for, and fish will absolutely love them. Now, let’s take a look at how to keep your Java Fern and some details about them.
Table of Contents
Quick Overview
| Scientific Name | Microsorum pteropus |
| Kingdom | Plantae |
| Family | Polypodiaceae |
| Care Level | Easy |
| Growth Rate | Low to Moderate |
| Maximum Size | 13.5 inches (35 cm) |
| Minimum Tank Size | 10 gallons |
| Temperature | 68-82°F (20-28°C) |
| pH | 6.0-8.0 |
| Water Hardness | 2-15 dKH (33.3-250.1 ppm) |
| Lighting | Low to Moderate |
| Substrate | Not necessary |
| Placement | Mid to background |
| Propagation | Adventitious Plantlet/Rhizome Division |
The Origin of Java Fern
The aquatic plant that goes by the scientific name Microsorum pteropus is originally from Southeast Asia. It is named after the Java island in Indonesia. This fern was first described by Carl Ludwig Blume, a Dutch-German botanist, in the year 1833.
You can find the Java Fern widely spread across many countries in Southeast Asia. From Malaysia, Thailand, the Philippines, and even India and some regions in China.
In nature, the Java Fern grows in coastal brackish regions, freshwater streams and rivers, and tropical rainforests. The ferns don’t need their roots buried inside the soil to live. Instead, they thrive on tree trunks, rocks, or ground.
As an aquatic plant, the Java Fern needs to stay in the water. They can be partially or fully immersed in the water.
Appearance
The Java Fern has an overall green coloration and is narrow in terms of shape. Generally, the Java Fern is composed of three basic parts: roots, rhizomes, and leaves.
The roots are dark brown in color and look like thin fuzzy hair or threads. They grow out of the rhizomes. In most plants, roots are usually responsible for absorbing nutrients for the plant to survive. For the Java Fern, the roots only function as an anchor. Meaning that it only needs to hold tight onto the fern’s medium so that they’re not swept away along with the water currents or wind.
Next are the rhizomes. These are dark green-colored roots-look-alike parts, but they actually stem. The rhizomes are the base of the ferns. They act as the plant’s nutrition absorber and perform the propagative means as well. The rhizomes will grow until they cover the entire surface of the object they are attached to. Normally, this part of the fern can reach 6 to 8 inches in width.
And now the main star, or we can call it the leaves. The leaves’ shapes differ per type, but all of them look similar. The leaves normally have bushy to spiky shapes and are hardy. In addition, they are also skinny and have a leathery texture. The leaves grow vertically and can reach a length of 13.5 inches.
As for the color, it’s typically medium to dark green. But the green shades very much depend on the amount of light they’re exposed to. The more light the leaves receive, the darker they get. You may also see brown or black bumps and black veiny lines along the leaves. If you do, it doesn’t mean that your fern catches a disease. It’s a sign that they’re mature and ready to propagate.
Java Fern Varieties
Java Ferns may come in various leaf shapes and sizes, even though all look almost similar. The leaves are typically pointy, but some may even look forked or twisted since there is a pretty wide range of variety. There are several different types of Java Fern, but here we have the most popular ones.
Narrow Leaf Java Fern
As the name suggests, this variety of Microsorum pteropus has thin and narrow leaves. Another feature is that it’s slightly wider towards the leaf base and tapered at the tip. As it matures, the leaves get twisted a bit. This Java Fern type can grow as tall as 12 inches, and the leaves size is around 4 to 8 inches.
Needle Leaf Java Fern
True to its name, the needle leaf Java Fern has almost needle-like leaves. They are even thinner than of the narrow variety, and the leaves are crinkly. They are also quite small in terms of size. This Java Fern type can only reach half the length of the narrow leaf, 6 inches. The true needle leaf is pretty rare and hard to find in the market.
Trident Java Fern
The trident Java Fern is even rarer than the needle leaf. This type is unique because the leaves are feathery and branched. Each leaf usually has 2 to 5 fingers. Compared to the narrow leaf, this type of Java Fern is shorter, but it grows faster. The trident Java Fern can grow up to 8 inches in height.
Windelov Java Fern
This Java Fern variety is even more unique than the trident. From the bottom, it may look like a regular Java Fern. But things get exciting towards the top of the leaves. The leaves are feathery, and the tips are finely branched, making some people call it lace java fern. As of height, the windeløv can grow up to 8 inches.
How to Plant Java Fern
It’s relatively easy to grow this aquatic plant. You won’t need any substrate since the Java Fern is not supposed to be buried. If you bury the rhizomes, they will rot, which will result in stunted growth and dying plant. What you need is an object to attach them to.
Preferable objects are rough-surfaced ones with cracks like cholla wood, driftwood, or lava rocks. Smooth-surfaced objects like glass or pebbles will take a longer time for the Java Fern to latch onto but can still work. Any size of mediums works, but bigger ones are better to give more room for the plant to grow and spread.
Once you have attached the Java Fern onto a medium, you need to secure them down to make them stay on the surface. You can tie the roots with a black fishing wire to match the color, but any color is just fine. After all, it’s the purpose that matters. You can also use zip ties or rubber bands.
After a few weeks, the Java Fern will already be firmly attached to the medium. This means you can remove the wire, zip ties, or rubber bands that you used to secure the roots. However, it is not necessary since the root will grow over time and cover up the ties.
As for placement, you can plant the Java Fern in the middle or at the back of the tank. They will cover the entire thing you have in your tank if you place them in the front.
You can also let the Java Fern float on the water surface. However, the rhizomes will not stop growing until they reach an object to latch onto. But you can always trim or prune it to keep your tank clean.
How to Care For Java Fern
The fern is one of the hardiest aquatic plants you can keep. However, it doesn’t mean that you can neglect and not care for them.
Although there are not many requirements that apply to the Java Fern, there are several things you can provide them to help them live and grow healthily.
Tank Size and Water Parameters
It’s advisable to grow them at least in a 10-gallon tank. But aquariums bigger than 10 gallons are more recommended since the Java Fern can easily crowd the tank.
As for water parameters, it is known that the ferns are adaptive and able to tolerate various water conditions. They can thrive in salty and brackish water, but freshwater is the most suitable.
Water temperature of 70-75°F will be best for them, but any temperature from 68 to 82°F (20-28°C) is tolerable. The ferns can tolerate a wide range of pH, starting from 6.0 to 8.0.
In addition, they can also thrive in soft to hard water. Java Fern really is one of the hardiest plants you can keep in a tank.
Lighting
Unlike other plants that require much light, this aquatic plant apparently is not a fan of it. If the Java Fern gets too much sunlight, it may develop brown patches and get burned. The leaves can even become transparent and slowly dissolving.
To achieve low and soft lighting for the plant, you can use soft fluorescents or small incandescent lights. 1.5 watts per gallon of water is what you need. If it’s still too much for your fern, you can reduce the upper lighting and back-lighting the tank with low-light LEDs.
Substrate & Fertilizer
As we have discussed earlier, the Java Fern doesn’t need to be buried. They prefer to have the roots and the rhizomes exposed to the water. Therefore, any substrate is not necessary.
As for fertilizer, the ferns can survive and thrive even without any fertilizer for complementary nutritions supply. But as they are a slow grower, providing them some supplements (fertilizer) may help their growth.
The fertilizer you can give the Java Fern may be different from the traditional plant fertilizer. It comes in liquid or tablet so that it’s easy to put into the water and safe for both fish and plants.
The liquid fertilizer may cloud the water and stimulate algae to grow, but it’s easily spread throughout the water. The tablet fertilizer, on the other hand, is not as easy to dissolve. That’s because you need to bury it inside the substrate and let it spread slowly.
Filtration & CO2
As one of the easiest plants to care for, the Java Fern doesn’t need any specific water filtration. The fern can absorb the nitrate in the water and live in low to moderate currents.
On top of that, this plant also doesn’t need CO2 to be able to survive and grow. But if you want to stimulate it to grow quicker, giving them an extra CO2 supply is a good idea.
Pruning
Java Fern grows slowly, so frequent pruning is not essential. Maybe once or twice a year. Pruning helps to boost plant development. You can prune your plant by taking off one or two largest leaves just above the rhizomes.
Because pruning encourages the plant to develop, it will result in a bigger plant after several times. You can also prune the leaf when you see a java melt starts to appear. It is a common disease targeting the java fern. We will discuss more of it shortly.
Propagation
Propagating the Java Fern is not a difficult task to complete. You don’t need to set up a separate tank or prepare any other requirements. In general, there are two ways for Java Fern to propagate.
First, they can produce their own plantlets. Sometimes it starts with black bumps. Then you will notice tiny plantlets starting to form on the edge of the leaves. After around 2 to 3 weeks, you will begin to see a few small leaves and the trailing roots.
You can pull the fresh plantlet off the parent using sterilized scissors or wait for them to fall off. They will then float around to find something to latch onto. You can also tie them down on a medium, as we discussed earlier.
Another way to propagate the Java Fern is by cutting the rhizome in half with a few leaves still attached. Again, you can secure them on driftwood or other decors. The cut rhizome will then grow by itself.
“Tank Mates” for Java Fern
This is another good news about the Java Fern. This fern is known to have tough and leathery leaves, which makes it not tasty and unappealing to fish. For this reason, your herbivorous fish won’t bother to give it a taste.
The plant is compatible to be kept together with both small and big fish such as Arowanas, Catfish, Cichlids, Plecos, and Tiger Oscars.
However, you should be careful if the plant is still in its early stage or freshly planted. Their roots are not fully developed and still not strong enough yet, so your fish might tear them apart. Especially if you keep larger and more aggressive fish together in one environment.
Even though the plant is compatible with many fish, there are several species you might need to avoid. Large cichlid species like Green Severum have been reported to be nibbling on the fern. It won’t be a good idea to house the plant together with the cichlid if you don’t want to see your plant getting torn apart.
Other aquatic species that are less compatible are large species of crayfish. They are infamous for destroying the plant with their claws.
Potential Problems
One most common issue with the Java Fern is the black spots or black lines along the leaves. On many plants, the appearance may be a sign of danger. But that’s not the case with the Java Fern! The black spots and lines are completely normal.
The dark bumps and black veins are not an issue. But there are a few actual problems that might target your Java Fern.
Diseases
One disease that targets the Java Fern is java melt. Several signs that indicate this condition are large brown or black spots, leaves turn mushy or transparent, and eventually rot and dissolve in the water.
There are a few factors that cause the java melt. First, the blue-green algae called cyanobacteria. The bacteria grows due to poor nutrition. If you see a layer of the bacterial film all over your plant and tank, this might be the cyanobacteria.
A way to eliminate it is by peeling off the filmy bacterial layers from the surfaces of your plant and aquarium. Then, you need to change 25% to 50% of the water and give fertilizer to the ferns. This will hopefully help to prevent the bacteria from coming back.
Another cause of java melt is excessive light. As we have known, the Java Fern doesn’t need much bright light. Too much of it can cause the leaves to turn translucent and melt away.
If this happens to your Java Fern, you can prune the damaged leaf immediately and turn all the lights in the aquarium off. After that, you need to cover the tank with a blanket or other covers to create a completely dark environment.
You can keep the tank covered for around three days to give your plant some time to recover.
Pests
There are not many pests or insects attracted to the Java Fern. If any, it would be little snails that live in plants. Some tiny snails are usually latching on the aquatic plant when you get them from a fish store.
Although they are not likely to damage the Java Fern, the snails can cause problems to your fish or other creature if you put them in your tank.
To get rid of the little snails, you can put one assassin snail to eat them. The assassin snail can then continue to live in the tank to help you clean the algae and leftover foods.
Other than that, there are really no more pests to concern. You won’t even see your fish nibbling on the fern and ripping them off. It’s because the leaves are tough, and it makes them unattractive to many aquatic creatures.
Is the Java Fern Suitable for You?
If you’re looking for an effortless aquatic plant, then you can consider getting a Java Fern. They are strong, don’t require much, and can be a good hiding place for your fish.
It doesn’t matter if you’re a beginner or an expert. The Java Fern will be a good pick for your aquarium. They don’t need a fancy aquarium setup and are easy to maintain. They will definitely survive in your freshwater tank.
On top of that, there are various types of them where you can choose from. It all depends on your personal pick and the plant availability. Considering some of them can be a bit hard to encounter.
So, are you getting the Java Fern? Or do you have any experience or tips you want to share with us? Please don’t hesitate to leave some in the comments!
