How To Care For Your New Java Fern: Planting, Propagation, Care & More

March 26, 2024

The Java fern is popular in freshwater aquariums due to its tough nature and stunning appearance. It’s an adaptable choice that can thrive in many different types of tanks, making it a very versatile option. Whether you’re a beginner or an experienced aquarist, a Java fern is an ideal plant to choose how to care for your java fern.

If you’re thinking about adding a Java fern to your tank, you might be wondering about how to plant it, propagate and care for it. In this article, we will take an in-depth look at the Java fern and how to ensure it thrives in your tank.

How To Care For Your New Java Fern: Planting, Propagation, Care & More

About Java Fern

Java fern (Microsorum Pteropus) is naturally found in Southeast Asia. It thrives in a variety of environments and can be found on rocks, roots, and tree trunks that are alongside bodies of water such as waterfalls or rivers.

The plant doesn’t only use its roots to find the nutrients it needs but can also use its leaves. Java fern grows both fully and partially submerged in water and will cling to textured surfaces.

Advantages Of Having Java Fern In Your Tank

As well as being an easy and hardy plant to maintain, there are many other advantages to having Java fern in your tank. It can actively help fish and invertebrates as the thick and dense leaves give fish a place to hide and feel safe.

This is invaluable for many fish who might feel threatened by their tank mates or just want some shelter and peace from a busy tank.

The leaves also provide enough cover to block out some of the light and many fish shelter under the Java fern leaves for this reason, also.

One of the main reasons for having any type of plant life in your tank is because of its effect on the water quality and Java fern is no different.

Fish take oxygen from the water and replace it with carbon dioxide as they respirate. Java fern takes this excess carbon dioxide, uses it to grow, and then replaces it with oxygen. 

Java fern also helps with the nitrate levels in your tank. It’s very important to keep a handle on the nitrate levels in the water as they can cause immense damage to your fish and even kill them if not kept in check.

As well as installing a powerful filter and regularly changing the tank water, a Java fern can help.

Java Fern Appearance And Growth

As we just learned, the most common type of Java fern has thick green leaves that can provide plenty of shelter. The leaves are very durable and won’t be easily damaged by your fish.

Some other varieties of Java fern have different shaped leaves that can be fatter or even more narrow. The leaves can be a variety of shades of green and may have brown spots or dark veins running through them.

This is nothing to worry about as the veining is very common, especially on mature leaves.

Java ferns grow slowly, but when fully mature they can be as tall as 13 inches and around six to eight inches wide. You don’t need to worry about regularly pruning or rearranging a Java fern because of this slow growth rate.

Caring For Java Fern

Java fern is an easy plant to care for and will adapt to most tank environments. It does have its preferences, however, and if you can ensure that the plant’s basic needs are met, it should thrive without much effort.

Java fern is suitable for beginners so everyone can soon have a well-established plant in their tanks. Let’s look at some of the things you should take into consideration.

Tank Size

For a single Java fern, it is recommended that your tank is at least 10 gallons in volume. If you plant a Java fern in a smaller tank, it’s likely that the plant’s growth will be stunted. 

If you’re considering planting several Java ferns, then you should go bigger. You don’t want to overcrowd your tank as this can have a negative impact on your fish and give them less room to swim and grow in.


Java fern is adaptable enough to grow in most lighting conditions. If you want to create the optimum environment for Java fern, however, then low to moderate lighting is the best.

Try to avoid any light that is too intense and bright as this can cause your Java fern to suffer. The leaves are prone to burning under these conditions and the burn spots will in turn lead to an increased chance of infection in the leaves.

Intense light can also result in the leaves losing their green color or even turning transparent. However, if the tank is too dark, it can stunt the growth of the plant.

A good level to aim for is around 1.5 watts of light for each gallon of water there is in the tank. Look for bulbs that have a color temperature around the 5,000 to 7,500 Kelvin range.

These levels should give your Java fern enough light without risking discoloration or burn spots.


It’s best to curate a tank environment that is as close to Java fern’s natural environment as possible. As stated earlier, Java fern is found in nature near bodies of water so it is used to having a strong water flow and a suitable amount of oxygen.

Java fern doesn’t need lots of additional carbon dioxide in the tank or any liquid fertilizer.

What Java fern does need, is the pH level, water temperature, and hardness. Luckily, the parameters it needs aren’t strict or difficult to manage. It prefers water that is soft, slightly acidic, and warm.

As long as your tank is within the parameters listed below, your Java fern should flourish.

  • ph level – 6.0 to 7.5
  • Temperature – 68 to 82 degrees Fahrenheit
  • Hardness – 2 to 15 degrees of carbonate hardness

The ideal temperature for a Java fern is in the mid-70s but it will remain healthy within the range listed above.


Luckily, this is not something of great concern when it comes to Java ferns. As the plant doesn’t draw nutrients from the substrate as most other plants do, it can even grow in bare-bottom aquariums.

Instead, it absorbs its nutrients through its leaves, and planting Java fern in a substrate can damage the plant instead of allowing it to thrive.

Although Java fern will survive short-term in gravel or soil, in the long term it won’t grow correctly and will eventually die.

How To Plant Java Fern

How To Plant Java Fern

As Java fern doesn’t need substrate to thrive, figuring out how to plant it can be a little difficult at first. It means that you have to try a few techniques that other plants don’t require but once planted, Java ferns are easy to care for. 

When you plant a Java fern, you need to consider the rhizomes. These look like roots and are dark and thin, but they don’t behave like roots and don’t like to be planted in soil or sand. You should think of them as anchoring stems instead of as roots.

In the Java fern’s natural environment, it is these rhizomes that enable the plant to grow on rocks and tree trunks as they anchor the plant in place.

Once secure, the rhizomes continue to expand and create a solid network to ensure the Java fern is kept in place.

You need to try and mimic this natural environment in your tank and this is why it’s best to attach it to a rock or piece of wood instead of planting it in soil.

Java ferns prefer surfaces that are rough and textured as opposed to smooth ones as they allow the rhizomes to get a firmer grip. If you choose a rock, make sure it isn’t smooth and polished as the rhizomes will struggle to attach to this.

We would recommend driftwood, lava rocks, or mineral slabs as these will all have the surface and textures that Java ferns love.

Some stores might sell Java ferns that are already attached to suitable items. This solves the problem for you, but you don’t have to stick with the store’s choice if it doesn’t suit your tank or you already have something in place.

To move a Java fern, you should tie down the rhizomes using fishing wire, rubber bands, or zip ties. It may not happen immediately, but with time the rhizomes will attach themselves to the new surface.

When they do, you can remove the ties that you used if you wish.

Trimming And Pruning

Due to the slow growth of Java fern, it’s not a plant that needs constant pruning. If you want a plant that you can put in your tank and allow to grow without much trimming and intervention, then Java fern is the ideal choice.

If you do want to prune it, you can, of course. Sometimes the way it grows doesn’t fit in with your tank or it can become too dense for your tastes.

If you do decide to thin out the leaves a little, the leaves should be cut as close to the rhizomes as you can manage. The Java fern will try to regrow but if you keep on top of it and prune new growth when it appears, you can keep it under control.

A fully mature Java fern only requires pruning annually unless you’re looking to thin out the leaves. Once a year you should look to remove any dead or discolored leaves and stop any overgrowth or unnecessary spread.

There is no need to do this more often than annually.

Java Fern Melt

Java ferns are adaptable, versatile, and easy to care for but they are still at risk of disease. When it comes to these plants, the main disease that you need to be wary of is called Java fern melt.

Java fern melt causes dark spots to grow on the green leaves. As the spots continue to develop, they turn to mush and then die. In some cases, even though the leaves have rotted away, the plant’s rhizomes aren’t affected and still remain.

This condition can develop rapidly and cause widespread damage to your Java fern, leaving it looking bare and weak before killing the plant completely. Java fern melt should be a major concern for any owners of the plant.

There are a few factors that can cause Java fern melt and ways to prevent it from occurring or spreading.


This is probably the most common cause of Java fern melt. As we stated earlier, too much light can damage a Java fern and in the most extreme cases, it can lead to Java fern melt.

To begin with, your plant will start to lose its color and begin to look sickly. As soon as you notice these symptoms, you should adjust your lighting.

You can also just turn the lights off for a few days so that the plant can recover. If you don’t act, then Java fern melt can set in.

Low Nutrients

Although Java fern doesn’t require fertilizer and can usually find its own nutrients, if you see Java fern melt starting to occur, you can add a little liquid fertilizer.

If the plant is suffering from a low level of nutrients, the fertilizer will help and the plant should recover.

Too Much Algae

If your tank has too much blue-green algae (BGA), this can also lead to melt. The bacteria responsible for Java fern melt is called cyanobacteria and it behaves like algae in the tank.

It can cover the leaves of your Java fern in a slimy, and thin film. If you find it in your tank it can be easily removed by being peeled off the plant or any other surfaces. The right balance of nutrients will prevent this bacteria from growing.

Tank Mates

Java Fern Tank Mates

Java fern is suited to share a tank with a wide variety of other plants and fish. As the leaves are thick and durable, they’re not easily damaged by fish that like to nip or get a little rowdy in the tank.

Even the most committed plant-eating fish struggle to munch their way through a Java fern and this leads to them not even attempting to nibble on the leaves.

When first planting a Java fern, it’s wise to exercise a little caution with the plant’s tank mates, however.

The rhizomes on new transplants can be weak and will take a little time to create a secure base for the plant so if you do have any fish that are particularly powerful and rambunctious, you may want to separate them from the Java fern until it has had time to become secure.

Once these early stages have passed, however, your Java fern will be able to withstand a beating!

Java Fern Propagation

Java ferns don’t reproduce through seeds, instead, they reproduce by apomixis. The fern creates replicas of itself that sprout on its leaves.

Mature plants can develop black spots on their leaves and these spots then develop into clones of the original plant over the course of several weeks.

You should leave this process to continue naturally and the longer you allow it to develop without intervention, the more growth there will be.

If you wait long enough, you will see tiny plants called plantlets begin to sprout. These will have their own leaves and rhizome systems.

When the plantlets have formed, you can remove them from the mature Java fern by carefully cutting them away using sterile scissors.

The plantlets can then be planted the same way any Java fern would be – by being anchored to a new surface. They will soon anchor and grow into a separate Java fern.

If you want to propagate your Java fern but no plantlets are developing, there is another method. This one can be difficult and doesn’t come without any risk, unfortunately, as it can risk damage to the existing plant.

Simply cut a rhizome in half and replant the cutting onto a new surface. Hopefully, it will anchor and grow the same way a plantlet would.

Final Thoughts

Java ferns are a versatile and easy to care for plant that can suit almost any tank and environment. The most difficult part of their care is their planting, as they don’t require any substrate and instead need a rough and textured surface to attach to.

Once the Java fern is in place and secured, its care becomes very easy. Keep the tank within the appropriate environmental limits and carefully monitor it for Java fern melt.

Java ferns only require annual pruning and can propagate endlessly to create a continuous supply of the plant.

Hopefully, the information and tips in this article will help you successfully plant and care for a Java fern in your tank.
Aleem Ahmed

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