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Java Fern Guide for Absolute Beginners: Plants Made Easy

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The Java Fern is a great aquatic plant for your household aquarium, especially if you are a beginner hobbyist. The plant offers several benefits for a fish tank and is one of the easiest plants to care for. 

The Java Fern, or Microsorum Pteropus, is a green- leafy plant that will grow even if just thrown in the water, quite literally. This plant only needs a few basic needs met such as the correct water parameters, nutrients, and lighting in order to thrive. 

Since the plant is so easy to care for, it is available in many aquatic and plant stores. It requires little to thrive but the more you know about the plant, the easier it is to care for it.

Types of Java Fern

The Java fern is a member of the Polypodiaceae family and has over 60 variants. However the most common is simply called the Java fern. It has thick green leaves that have the texture of leather. This makes the plant very resilient and great for tanks with larger fish. The fern usually grows to about 14 inches.

This is a picture of the most common type of Java Fern:

Microsorum pteropus in front of white background

Narrow Leaf Java Fern

With that being said, you may be lucky to find some of the rarer types of Java ferns as well.These include the Narrow-leaf Java fern, Windelov Java fern, Needle leaf Java fern, and the Trident Java fern.

The Narrow leaf Java fern has narrow leaves compared to the original and they grow at a steeper level. This makes them perfect for taller tanks since they can also grow up to a foot tall. 

Windelov Java Fern

On the other end of the spectrum comes the Windelov Java fern. They do well in smaller tanks because they are smaller than other variants; only growing about 8 inches tall. 

Their leaves are also split into three smaller leaves, which makes them look like forks. This can add a unique design element to your aquarium. 

Needle Leaf Java Fern

The Needle leaf Java fern is unique because the leaves are much thinner than its counterparts and only grows about 6 inches tall. This also makes this fern great for smaller tanks. However they can be a bit harder to find than the other variations.

Trident Java Fern

The Trident Java fern is the rarest variation of them all. Instead of thick leathery leaves that are resistant, this fern has feathery, lobed leaves. This fern is also much shorter than the other. 

However, it is not great for small tanks because it grows rather quickly compared to the others. It can also be quite difficult to find and more expensive than the others as well. 

Java Fern Basic Needs

While the Java fern is incredibly easy to care for, they do require a few basic needs to be met in order to thrive. This includes having the correct water parameters, correct nutrients, and lighting in the tank.

Water Parameters

The Java fern is a freshwater plant and should not be placed in any saltwater aquariums. With that being said, the fern is a pretty hardy plant but does best in certain parameters. These include:

  • Water Temperature: 68–80ºF
  • Acidity:  6.0–7.5pH
  • Water Hardness: 3–8 dGH

Again, the plant is hardy and a quick drop or increase in these numbers won’t kill the plant, but you should keep them as steady as possible. As you can see, the plant prefers warmer tropical water, but it can do fine in colder water as well. For instance, it could still do well in a goldfish tank.


While some plants need a good fertilizer for nutrients, the Java fern does not. This plant can pull nutrients out of the water which means you don’t need to take the extra step in feeding it. These nutrients come from leftover fish food, fish waste, and other components in the tank.

However, if you wish to grow your fern at a faster rate, you can add a bit of liquid fertilizer to the tank during a partial water change. Just be mindful of what the bottle says to ensure your fish do not end up sick. 


In nature, the Java fern typically grows in low-lighted areas such as caves or on the jungle floor. This means that they do not need as much lighting as other aquatic plants. They need about 6 hours of light per day. If they receive more lighting than this, it can cause their leaves to turn brown. 

It is also recommended that you use a subdued fluorescent light. This will offer dimmer lighting and won’t over light the plant. 

Tank Requirements

Aside from the above basic needs, the Java fern does have a few other tank requirements that need to be met in order for them to thrive to the best of their ability. 

Tank Size

While the sizes of the different Java ferns can vary, it is safe to say that the smallest tank you should have is a 10-gallon tank minimum. However, the bigger the better; especially if you want your plant to grow to the biggest it can. 

With that being said, if you do have a 10 gallon tank, you will want to make sure there are not too many decorations so you have room for the plant and your fish community. If it is too overwhelming in the tank because of too many items, it could stress your fish and also choke the growth of your plant.


As mentioned, the Jave ferm does not need much to survive. Substrate is not needed in a tank with the Java fern as it can thrive with a bare bottom tank. With that being said, if you do have substrate in your tank, you will want to make sure you do not place the roots of the plant in the substrate, as this can cause the plant to rot.

Instead, you can attach the fern to a rock of decoration above the substrate, or better yet you can even let it float at the top of your tank! This is perfect for guppies or other mid level and top level fish. 

How to Propagate Java Fern

The Java fern typically only grows about an inch per month so it does not have as fast of a growth rate as other plants. However, when it has fully grown, you may want to propagate the plant into other aquariums. There are two simple ways to do this!

  1. Cut off sections of the rhizome (bottom layer of the plant) that still has a few plants attached to it. Then place these plants in the new tank with anchors so they grow where you want them to. 
  1. Wait for your current plant to develop black spots. While you may think these spots mean your plant is rotting; this is not the case. The black spots are actually baby Java ferns. Once sprouted, you can cut the tiny ferns and replant them where you would like to.
Java fern tied in bogwood over white background

Benefits of Java Fern in Your Aquarium

SInce the Java fern is so easy to care for, you may think that there are not many benefits to having this. This couldn’t be further from the truth. There are several benefits to having these plants in your home aquarium. These include: 

  • Aquascaping. We all love to design our fish tanks to show a bit of our personalities and likings. The fern allows us to do that by giving a natural look to the tank. The best part is you can anchor this plant wherever you’d like in the tank or let it float on top.
  • Reduce carbon dioxide. Java ferns will naturally reduce the level of carbon dioxide in your fish tank. This will help you keep your tank parameters in check and also keep your fish healthy. 
  • Provide hiding places. Many species of fish love to hide, whether it be from predators, or they may be playing in plants and exploring. Regardless of the reason, the Java fern provides plenty of hiding places and shelter for smaller species such as shrimp or snails. 
  • Adds oxygen to the tank. Oxygenation is important for fish and plants. If there is not enough oxygen in the tank, fish will suffocate and the plants will not thrive. While you can add bubblers and filters to increase air flow, the Java fern is also a great additive to get the job done naturally. 

Common Problems Correlating with Java Fern

While these plants are simple to take care of, there are a few common problems that can happen and are avoidable. These are:

  • Java fern melt. This happens when there is too much lighting in the tank and will cause your fern to have larger brown spots that turn mushy. To fix this, you will have to trim off the spoiled parts of the plant and reduce the lighting in your tank to prevent it from getting worse. 
  • Substrate poisoning. As previously stated, these plants should not be placed in a substrate, If they are, the rhizome will rot and cause the plant to turn brown. Substrates should be completely avoided.