Java Fern Care (Microsorum pteropus) Guide For Aquariums

Java fern: super popular, looks great, and is pretty simple to care for.

In fact, java fern is one of the first plant species I ever tried to grow and propagate in my planted aquarium. I love it and have had great success with it.

In this guide, I’m going to share my knowledge and experience with you about this popular aquarium plant.

You’ll learn everything you need to know to be successful, even if you’re a complete beginner.

Java Fern Overview

  • Scientific Name: Microsorum pteropus
  • Higher classification: Microsorum
  • Kingdom: Plantae
  • Family: Polypodiaceae
  • Care Level: beginner
  • Growth Rate: slow
  • Tank Placement: mid to background
  • Lighting Requirement: low
  • Ideal Temperature: 70°-83°F (21.1°-28.3°C)
  • pH: 6.0-8.0
  • Water Hardness: 2-15 dKH (33.3-250.1 ppm)

Java fern (microsorum pteropus) is an aquatic plant native to parts of Southeast Asia. It was first described by Dutch-German botanist Karl Ludwig Blume in 1833.

It grows along the banks of freshwater rivers and streams in Thailand, Malaysia, India and China.

It is a true aquatic plant, meaning that it can grow and thrive while completely immersed in water. It can also be grown with the leaves sticking out of the water, but the rhizome and roots have to stay underwater at all times or the plant will dry out and die.

Plant Structure

Kate holding potted java fern on white background

Java fern has three basic parts:

Leaves – these can be anywhere from ¼ inch to 12 inches long. In the natural form of the plant, the leaves are bright green, long, narrow and pointed

Rhizome – rhizomes look kind of like dark green roots, but they’re actually stems. They grow along the surface of whatever the Java fern is attached to.

The leaves grow out of the top of the rhizome and the roots grow out of the bottom. The rhizome is what absorbs most of the water and nutrients the plant needs.

Roots – dark brown, fuzzy roots grow off of the rhizome. But instead of absorbing nutrients, these roots mainly function to anchor the plant to something, like a log or rock, and keep it from being swept away in the current.

Java fern is an epiphyte, meaning its roots attach it to something, like a piece of driftwood or tree roots, instead of rooting itself in sand or soil.

Most plants draw water and nutrients from soil through their roots. However, Java fern works a little differently. It pulls these directly from the water column, instead of from underground.

Reproduction

Java fern reproduces by a process called apomixis. Instead of producing seeds that need to be fertilized, Java ferns clone themselves.

Underneath the leaves of mature plants, tiny baby plants, called plantlets, start to grow. Each plantlet is a perfect replica of the adult plant.

The plantlets develop roots and several small leaves. Eventually, they break off from the adult plant and get washed downstream until they can attach themselves somewhere and start a life of their own.

Varieties

You may see Java ferns available that have different leaf shapes. Some leaves may be forked, narrow or even twisted.

Despite these differences, they’re all still considered to be the same species.

I know, it’s weird, you would think each one would be its own species. But clearly, the scientific community did not consult me on this decision.

They are all listed as Microsorum Pteropus, but with the variety name in quotation marks after the scientific name (e.g. Microsorum Pteropus, “Trident”).

Microsorum Pteropus, “Narrow Leaf”

Narrow leaf Java fern has much thinner leaves. As the plant matures, the leaves get a slight twist to them that looks really interesting.

Microsorum Pteropus, “Needle Leaf”

The leaves on needle leaf are even thinner than narrow leaf. The long thin leaves look almost crinkly and it’s hard at first glance to tell it’s even Java fern.

Microsorum Pteropus, “Trident”

Instead of the leaf coming to a single point, each one is forked with several fingers coming off the main leaf, kind of like the trident carried by Poseidon.

Microsorum Pteropus, “Windeløv”

The leaves on Windeløv look the same as regular Java fern until it gets to the ends, which separates into a bunch of frilly forks that curl around on themselves.

The first time I saw one, I thought a hungry fish had come by and shredded the plant! The look has grown on me, though, and I think it adds an interesting texture to the tank.

Caring For Java Fern In Aquariums

Close up of java fern on white background

Java fern is really undemanding and doesn’t require a fancy set up at all. Basic lighting and minimal fertilizing is more than enough to make it mature into a healthy plant. You don’t have to drop a bunch of money on a CO2 setup, either.

It’s slow growing, so it doesn’t eat up a ton of excess nutrients out of your water, but it does use up at least some of the nitrates (NO3-) in your tank, helping to keep the water column clean.

Aquarium Size

I really wouldn’t put Java fern in a tank smaller than 10 gallons. It grows slowly, but it can eventually get pretty big.

I have mature ferns with leaves that are almost a foot long (30 cm) and the base of the plant is easily 8 inches (20.3 cm) around. That plant would completely overrun something like a 5 gallon.

Water Parameters

This plant really is not picky about water parameters. It can tolerate water that ranges from very soft to moderately hard, as well as a wide pH range.

I’ve seen it used in blackwater tanks with almost no hardness and a pH of 6.5. I’ve also seen it do just as well in hard water with a pH of 8.0.

That’s the beauty of Java fern, it works for just about anyone, in any set up.

Lighting Requirements

Java fern only requires low light (PAR <50). It will happily grow in light that would completely kill other kinds of plants.

It can also tolerate more intense light and it will grow more quickly under brighter lights. But it’s not a requirement.

Using Fertilizer

You don’t have to use fertilizer with Java fern. But, it will grow much more quickly if you use a liquid fertilizer like Seachem Flourish or API Leaf Zone.

As for myself, I dose my tanks twice a week with the recommended amount of Flourish and have seen great results.

When I first got into live plants, I thought that my lights were too weak to even grow Java fern. It didn’t die or anything, but it didn’t really grow either.

But then I started adding the liquid fertilizer and the ferns and my other plants started going crazy. The Java fern will still grow more slowly than other kinds of plants, but you’ll start to notice a major difference from month to month.

Using CO2

You don’t need CO2 to grow Java fern. Of course, it will grow quicker if you do use it. But frankly, I’ve grown so much Java fern over the years that I’ve had to give some away to friends because I ran out of room for it. And I don’t use CO2 in any of my tanks.

How to Plant Java Fern

Java fern unpotted

One of the things that I truly love about this aquarium plant is that it will grow just about any place in the tank. Since it doesn’t need to have strong light, or to be down in the substrate, you can jam it just about anywhere and it will grow.

The trick with Java fern is to weigh it down so it will stay where you want it in the tank. Otherwise, it will just float around in the tank until it finds a spot it likes, usually stuck to the filter intake.

Most people tie it to a rock or driftwood, or even resin decor with cotton thread or fishing line. Since Java fern is a epiphyte, its roots are really good at anchoring the plant to just about any surface they touch.

All you have to do is loosely tie the rhizome to your decor, like a piece of driftwood, cholla wood, rocks, shells, etc. After a few weeks, the roots will grab a hold on the decor and you can remove the string or fishing line.

Kate gluing java fern to driftwood

Everywhere you look, you’ll see sources that tell you not to bury java fern down in the substrate because it will rot.

In my experience, this is true and false. So, you don’t want to bury the rhizomes down in the gravel, they will definitely rot over time.

But, if the fuzzy roots are long enough, you can cover them with just enough gravel to weigh the plant down. After a few weeks, the roots will stick to the gravel, even if you pick the plant up, the roots will hold on to a ball of gravel.

Then you can place the plant anywhere you want and the gravel will weigh it down. I use this trick a lot when I have baby Java fern and don’t have anything available to tie them to.

Also, if you have decor that has little openings in it, you can stuff pieces of Java fern down into it and it will grow there. I do this with resin decor all the time. Since I have an endless stream of plantlets, I put them in little swim through holes that are too small for my fish.

How to Maintain Java Fern

This hardy little plant doesn’t need much maintenance. Occasionally you’ll have an old leaf die off. Just pinch it off as close to the rhizome as you can get and toss the dead leaf in the trash.

Java Fern Melt

Sometimes, multiple leaves can start to turn yellow or brown, get mushy and die back.

This is really common when it is first added to a new tank. The old leaves have a harder time adjusting to the new water conditions, especially if it was grown from a tissue culture.

It’s best to trim any browning leaves down to the rhizome. Usually, the plant will get acclimated to your water and start putting out new leaves.

I’ve also found that I’ve had more trouble with Java fern melt when I wasn’t dosing any kind of fertilizer.

After I started dosing a comprehensive liquid fertilizer once a week, I stopped having any kind of melt. My plants rarely even lose old leaves.

Brown Spots Under Leaves

This one isn’t really even a problem, but people see it and get a little freaked out.

Rows of dark brown or black spots on the underside of leaves is nothing to worry about. It just means the adult plant is about to put off plantlets. Usually, each spot will become a baby plant.

Yay! New plants for free!

Propagation

Plant propagation is the process of growing new plants by germinating seeds, rooting cuttings or splitting bulbs/rhizomes.

Propagating Java fern is really simple. Frankly, it usually does a great job of propagating itself. Once you see plantlets start to form on the edges of leaves, just wait until they have formed several leaves and trailing roots.

Then you can pull them off the parent plant tie them to driftwood or other decor. They’ll start to grow on their own with very little fuss.

Or you can snip off a section of rhizome with a few leaves attached. Each piece of rhizome you cut off will become a new plant. You can tie or weigh them down in the tank and they’ll start to grow.

Java fern plantlet growing on a leaf

Buying Java Fern: How to Choose a Healthy Plant

Java fern in packaging

Double check for leaves that are browned around the edges. The entire leaf should be bright to dark green.

Also, take a look at the rhizome. A healthy rhizome should be a dark green without any kind of browning.

Usually, Java fern is sold as a cutting from a larger plant, with only a few leaves attached to a piece of rhizome. The leaves may only be a few inches long. This is completely normal.

As the rhizome grows, it will put off new leaves that will get bigger as the plant matures.

What Fish Can I Keep With Java Fern?

One nice aspect of Java fern, apparently it’s not very tasty. This is a good thing. It means that a lot of herbivorous fish, like plecos, won’t completely destroy your ferns to eat them.

My clown pleco loves to tear apart other plants in my tank, but leaves the Java fern alone completely.

Now, some species will tear it apart anyway, I had a very large green severum that did destroy and eat the Java fern, along with all the other plants in my tank.

So it’s not an absolute guarantee, but it’s got a better shot than most other plants to survive fish that think live plants in the tank are a salad bar.

Is Java Fern Right for You?

When to comes to aquarium plants, I really can’t recommend this plant highly enough. It was the first species I ever tried to grow and I’ve had great success with it.

I bought one small piece years ago and I’ve been able to propagate it so many times that my tanks are full of it, even after giving a bunch away.

Java fern really is easy to take care of, you don’t need a fancy set up and it’s practically bombproof.

There are several different varieties available so you can have different shapes and textures in your tank to make things more interesting.

It really is a great addition to your tank and your fish will love it!

Katherine Morgan
Katherine Morgan

Hey, there! I'm Katherine from Northwest Florida. An aquarium specialist, I've kept tanks for over two decades, enjoy experimenting with low-tech planted setups and an avid South American cichlid enthusiast.

10 Comments

  1. Thanks for the help n in plain English to. I’m thinking about changing from fake to live plants but was worried it would be tough. Slowly but surely I think I switch.

  2. Helpful article in length, organization and mix of topics related to the Java ferns. Wish I had known how foolproof a beginners aquatic plant they are when I started out several months ago! Began an aquarium as a new hobby last year, learning as I went, doing it as cheaply as possible. So was pleased that, as a novice, managed to created a healthy, stable, diverse DIY tank. Became so confident that I thought I’d try my hand at live plants, replacing a tank full of plastic fake ones. Yikes–has been far more difficult than setting up the tank in the first place! Have made lots of novice mistakes, with few plants actually thriving–except for Java ferns, which I learned about more recently. They have been so robust and ‘idiot proof’, even I didn’t kill them. My Java ferns grow relatively slowly (I do or add almost nothing extra to help my plants grows except vigilant pruning of dead or dying leaves, mainly out of fear of messing up the water chemistry that has stayed balanced and work just right for all the other creatures in the tank!). But I’ve found that also has meant when any problems popped up with them, it happened slower too–I had time to figure out what was wrong, and there have been no dead-within-days ‘die offs’ of my Java ferns like I’ve had with some other plants! And I totally agree about their popularity with fish. They seem to be the most widely favoured by the animals in my tanks (the tetras, gouramis, kuhli loaches, guppies, endlers, zebra snails, bloody mary shrimp all eat algae off them or hide in them, and my African dwarf frogs love to sleep up on top of their leaves just below the surface). Yet they are maybe the only plant that I haven’t had issues with being either eaten, rooted up, or otherwise destroyed somehow by some tank dweller or another.

  3. Thank you so so much for your article very helpful I have plantlets wasn’t sure what to do with them but now I do, looking forward to watching them grow

  4. I’ve just got my first Java Fern,
    Thank you for the article

    This is becoming my favorite website about fish keeping, every article is very detailed and well written.

  5. A VERY INFORMATIVE AND USEFUL ARTICLE-THANK YOU. HOPE YOU CAN DO ARTICLES ON OTHER “EASY” AQUARIUM PLANTS SUCH AS JAVA MOSS AND OHER EPIPHYTES

  6. Wish I would have seen your article before Christmas’22. I already have the plantlets growing. And several of the leaves have the black spots started. I have been pulling them out from being buried and trying something else bc I was worried about the root rot. But after your article. I think I’m going to let them grow roots to attach then move above substrate. Thank you

  7. I absolutely love keeping Java Fern! For all wondering, it is not goldfish proof, they destroy it every time!

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