Java Fern Ultimate Growing Guide 2022 (growing, feeding & propagating)

Java Fern, which goes by the scientific name Leptochilus pteropus, has been one of the most popular plants in the freshwater fishkeeping hobby for many years. This highly variable fern-like plant is famed for its ease of growth, unique leaf structure, and unusual way in which it anchors itself to rocks, wood, and decorations in the tank.

Although Java Fern looks delicate it is actually a very hardy plant that can cope with a wide range of water parameters.

Java Fern is an ideal plant for those who are new to aquarium plants but is also popular with professional aquascapers. I myself have Java Fern in dozens of the tanks in my fish room and I keep it in tanks with a wide selection of fish, from tiny Ember Tetras to some very large Fantail Goldfish.

Overview of Java Fern

Java Fern was given its common name after the Indonesian island of Java. Java Fern can be found growing in freshwater rivers and streams in many parts of Thailand, Malaysia, China, and Northeastern India.

Java Fern is an easy-to-grow plant that requires only low light levels, no additional CO2, and little in the way of routine maintenance.

The tough, dark green, fern-like leaves of Java Fern grow to around 12″ (30cm) long, extending from a stem that runs horizontally rather than vertically. Typically Java Fern can be found growing on rocks, wood, and aquarium decorations rather than planted in the substrate.

Java Fern uses its strong roots to anchor itself in place. In one of my own aquariums, it has even attached itself to the side of the internal aquarium filter, where it now looks stunning and hides the filter.

Java Fern Characteristics

Common Name:	Java Fern
Scientific Name:	Leptochilus pteropus (formerly Microsorum pteropus)
Family:	Polypodiaceae
Origins:	Thailand, Malaysia, China, and Northeastern India
Care Level:	Easy
Growth Rate:	Slow
Light Level:	Low
C02 Level:	Low
Tank Location:	Foreground or Midground
Temperature:	68°F – 82°F (20°C – 27.5°C)
Color:	Dark green
Propagation Method:	Rhizome division
Maximum Height:	12″ (30cm)
Minimum Tank Size:	10-gallons (38 liters)

Java Fern General Description

Java Fern is a hardy plant that boasts dark green, fern-like leaves which extend directly up from its rhizome stem, which grows in a horizontal direction rather than vertically like in most plants. The color of the leaves varies from light green to dark, almost bottle green. Often the more light that Java Fern receives the darker the leaves become.

The leaves are tough and have raised veins running from their base to the tips. The leaves feel rough to the touch and are some of the toughest leaves you will find in an aquarium plant.

Although typically grown submerged, Java Fern is also capable of growing partially submerged. In the wild, it can be found growing under or very close to waterfalls as well as in damp and humid forest locations. In some regions, it has also been recorded growing directly on tree trunks.

The wiry hair-like roots that grow from the rhizome cling to whatever the Java Fern is growing on, holding the plant firmly in place meaning it can even cope living with boisterous fish like Fancy Goldfish, Oscars, and even some of the larger South American Cichlids.

https://youtu.be/m1wU9gzaO44

Different Types of Java Fern

As well as the regular Java Fern, there are essentially another 5 varieties of Java Fern that are commonly available to hobbyists. These are;

Last update on 2024-12-30 / Affiliate links / Images from Amazon Product Advertising API

Ideal Tank Conditions for Java Fern

Java Fern is such an easy to grow and hardy plant that its ideal tank conditions could just be listed as wet! Java Fern does not require any special lighting, nor does it need the addition of CO2. It isn’t too fussy about pH and can stand a wide variety of temperatures. It is essentially a bulletproof plant.

With that said, below I have detailed what in my experience of growing this plant are the ideal tank conditions.

Temperature

In almost every book you read about Java Fern, the ideal temperature range is listed as 68°F to 82°F (20°C to 27.5°C). This is a pretty wide temperature range, but truth be told, it will happily grow in water that is both cooler and warmer than these temperatures.

I currently have Java Fern growing in Fancy Goldfish tanks which run at around 64°F (17.5°C) and I have it in a number of Discus tanks that are closer to 84°F (29°C).

I wouldn’t be surprised if it kept growing even outside of those temperatures.

Lighting

Java Fern could not be less fussy about lighting. Providing it receives some light, it will grow. The majority of the tanks in my fish room run on Fluval Aquasky lights, which grow plants really well, but I also have tanks with regular shop lights above them and some that run on low-energy CFL bulbs.

In my experience, providing you have a light running above your Java Fern tank that is on for around 8 to 10 hours a day, Java Fern will grow well for you.

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Substrate

Unusually, Java Fern does not need a substrate. In fact, if you plant it in the substrate there is a good chance it will die off.

Java Fern grows by attaching itself to rocks, wood, roots, and aquarium decoration. As such, Java Fern does not care at all what substrate you have in your aquarium.

CO2 Injection

I run a number of tanks that have CO2 injection with Java Fern growing in them, and about twice as many that don’t have CO2 but also have Java Fern. I don’t think there is any discernable difference between those that have added CO2 and those that don’t.

As such, I can confidently say Java Fern does not need CO2 to be injected into its tank.

How to Grow Java Fern

As mentioned previously, Java Fern does not like to be buried. Instead, it naturally chooses to attach itself to rocks or pieces of wood. In the wild, small pieces of Java Fern would float around in the river or stream until they came to rest in a suitable location, where they would put down roots and anchor themselves in place.

In our aquariums, we typically don’t want pieces of Java Fern drifting around in the water until they end up somewhere suitable to grow. Instead, we can tie bits of Java Fern directly to rocks or pieces of wood.

Over the years I have used fishing line, string, and zip ties to hold pieces of Java Fern in place. Anything will do the job, but black zip ties are probably my favorite as they last forever and are almost invisible once the Jave Fern Grows over them.

To fasten Java Farn to a piece of wood or rock, I usually start by cutting a small piece of rhizome off the main piece of Java Fern. I then carefully place the piece of plant on the wood and wrap a tie wrap around the rhizome and wood, taking care not to tighten the tie wrap so much it damages the Java Fern.

Typically I will repeat this process until the rock or piece of wood is covered. I have found that cutting a larger piece of Java Fern down and spreading it out along the length of whatever I am tying it to creates a better effect in the long run than just tying a single lump of Java Fern to the wood.

In theory, after about 6 to 8 weeks the Java Fern will have set down a good group of roots that will fasten it to the wood or rocks and you can remove the zip tie or fishing line.

However, in my experience removing whatever you have used to fasten the Java Fern down only ends up causing damage to the plant. I would advise just leaving the fishing zine or zip tie in place forever.

Fertilizing Java Fern

Java Ferns take in all the nutrients they need directly from the water column. As they are not growing out of the substrate, they can’t rely on the dirt and detritus that builds up in the gravel as a source of food.

https://youtu.be/AWBBtV6mAvw

Java Fern Maintenance

Java Fern is probably the easiest aquarium plant to grow, and as such, there is very little routine maintenance to carry out.

Occasionally, one or more Java Fern leaves may turn brown and the best course of action is to cut these individual leaves off. If a few leaves start to turn brown it may be a sign of a wider problem. See more on Java Fern problems below.

If your Java Fern is really happy and growing well you might need to trim it back. Trimming a Java Fern is really very easy, you simply take a sharp pair of scissors and cut anywhere along the horizontal rhizome. After you remove the excess piece of plant you can either tie it to another rock or piece of wood, or you can give it away to a fellow hobbyist.

Java Fern is usually fair slow to get going, but once it is settled and happy it can grow at quite a pace, so it may need trimming two to three times a year depending on the size of tank and space available.

Propagating Java Fern

Java Fern is incredibly easy to propagate. It doesn’t require any special equipment or knowledge, just a sharp pair of scissors.

There are in fact 2 different ways to propagate Java Fern. The first is by cutting the rhizome and the second by removing the tiny little plantlets that develop on the leaves of the Java Fern.

Cutting the rhizome

Cutting the rhizome is simply a case of snipping anywhere along the length to make one plant into two.

Java Fern will grow from even really very small pieces so you can take a single Java Fern plant and cut it into 20 or 30 smaller plants. Each one will then grow.

This is a great technique when you want to cover an entire piece of bogwood in Java Fern. Just cut a plant into tiny pieces and tie each piece individually to the wood. Within 3 to 4 months the piece of wood will be a mass of Java Fern.

Plantlets

The other way to propagate Java Fern is via plantlets. Plantlets are little tiny Java Fern plants that naturally develop on the main Java Fern plant. These fully formed, but very small plants grow on the main Java Fern, then naturally break off and float through the water column looking for somewhere to settle and grow.

Releasing plantlets is the main way Java Fern propagates itself in the wild.

I have a tank with a group of Fancy Goldfish. In the tank, I have Java Fern that has naturally colonized the casing of the internal filter where plantlets have attached themselves and grown.

What Other Plants Can Grow With Java Fern?

I think it is fair to say ANY plant that will grow in a tropical fish tank can be grown with Java Fern. Java Fern is tough and will not be outgrown by any other plants. Even if it finds itself growing in the shadow of a larger plant, it will still do just fine.

I currently grow Java Fern in tanks with;

As well as a few other species. I do find the shape of Java Fern leaves look amazing against some of the finer leaved plants like Water Wisteria and Ammannia Gracilis.

What Fish Can Live With Java Fern?

I think the simplest answer to this question is just about every fish can live with Java Fern. I am struggling to think of any fish that couldn’t live in a tank with Java Fern.

In my own fish room I currently have the following in tanks with Java Fern;

What Fish to Avoid with Java Fern?

As mentioned above, I don’t think I can think of any fish that could not be kept in a tank with Java Fern growing in it. Even known herbivores like Tinfoil Barbs, African Cichlids, and Common Goldfish are generally safe with Java Fern as the Java Ferns leaves are so tough.

The one caveat is that the Java Fern must be well attached to whatever it is growing on. If you tie a fresh piece of Java Fern to a log, then add it to an Oscar tank, the Java Fern may well get knocked off. If however, it is well-rooted in place, it won’t go anywhere.

Benefits of Growing Java Fern

In my experience, growing any live aquatic plant has three major advantages. Firstly, I absolutely believe live plants make an aquarium look far more natural. Although there is nothing natural about the collection of fish we keep together, somehow live plants make it feel real!

The majority of fish we keep just look brighter and more colorful against a background of green.

Live aquatic plants also absorb excess nutrients like ammonia and nitrate from the water. When fish go to the bathroom, their waste is very high in ammonia, and ammonia is toxic to fish. Live plants, including Java Fern, absorb the ammonia.

The third, and in my opinion best benefit of growing Java Fern in my aquariums is the Java Fern leaves give baby fish somewhere to hide. I breed a lot of livebearers, and adding a large clump of Java Fern to their aquarium increases the chances of baby fish not being eaten by their parents.

Common Java Fern Problems

Java Fern is not really a plant that suffers from many problems. It really is a low-maintenance plant. There are however a couple of common problems Java Fern growers can have to deal with.

Buried Rhizome

The most common issue is caused by the fish keeper themselves. Java Fern should NEVER be planted directly into the substrate. If the rhizome is buried it will rot, killing the Java Fern within a few weeks.

If you discover your Java Fern is struggling and is planted directly into the substrate, pull it out ASAP and instead tie it to a piece of rock or bogwood. Hopefully, the Java Fern will quickly recover and begin to grow strongly.

Brown Leaf Spots

Probably the second most common issue people have with their Java Fern is brown spots under the leaves. Often new fishkeepers will see these spots and panic thinking their Java Fern is diseased. I have even spoken to people who have pulled out their Java Fern and thrown it into the trash because of brown spots.

These brown spots are actually nothing to worry about. In fact, they are a sign your Java Fern is growing Java Fern plantlets. It means you have a happy Java Fern.

Java Fern Melt

Java Fern Melt is the name given to the phenomenon whereby all or most of the leaves on a Java Fern plant suddenly turn brown and rot away. Java Fern melt happens most often just after a plant is added to a new aquarium.

Many Java Fern plants are grown emersed (meaning out of water) before being sold to aquarists. When we put these emersed-grown Java Ferns into our tanks, the plant has to convert from being emersed grown to submerged grown. To do this it will drop all its leaves and grow new ones.

If your Java Fern is new to you and has turned brown over a very short space of time, do not worry, just leave the plant alone and it will probably grow new, bright green leaves.

The great news is, Java Fern grows slowly, but also dies slowly, meaning if you discover something is wrong you will have time to discover the issue and make it right before the Java Fern dies.

Where to Buy Java Fern?

Java Fern is ubiquitous throughout the hobby and should be available to buy in any half-decent local fish store. Most stores carry only the standard forms of Java Fern in stock, but the more exotic may require a little more searching.

Last update on 2024-12-30 / Affiliate links / Images from Amazon Product Advertising API

In Conclusion

I have been growing Java Fern for almost my entire fish-keeping career, a period now well over 30 years. Java Fern is hardy, versatile, and fits well into just about every tank setup I can think of. It can even be grown with fish that are traditionally thought of as plant destroyers.

Even adding a small piece of Java Fern will enhance your aquarium and make your tank look and feel better.

Article Sources:

https://en.wikipedia.org/wiki/Polypodiaceae

https://en.wikipedia.org/wiki/Leptochilus_pteropus

https://www.aquariumcoop.com/blogs/aquarium/java-fern-microsorum-pteropus-an-easy-aquatic-plant