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I am fairly sure, with the possible exception of algae, Java Moss is the easiest plant to grow in an aquarium. Simply place it in water, give in some light and some nutrients, and Java Moss can’t help but grow.
Not only is Java Moss really easy to grow, but it is also possibly one of the most desirable plants for anyone wishing to breed tropical fish or Red Cherry Shrimp. Java Moss is also incredibly desirable for those in the aquascaping world. Java Moss can be grown and shaped to look like bushes, trees, and even clouds.
Overview of Java Moss
Java Moss is unlike any other plant in the aquarium hobby. It doesn’t have any roots. Java Moss simply forms a loose bundle of greenery that either just sits on the bottom of the tank, or can be attached to wood, rocks, and decorations within the aquarium.
Java Moss is by far the most grown moss in the hobby. There are a number of other species of moss available, and some are often confused with Java Moss.
Java Moss is a bright to dark green color and as it grows it forms a potentially huge mass of moss that can easily fill a 40 or 50-gallon (190 liters) aquarium if left unchecked.
Java Moss Characteristics
|Common Name:||Java Moss, Bogor Moss|
|Scientific Name:||Taxiphyllum barbieri|
|Temperature:||64°F – 86°F (18°C – 30°C)|
|Minimum Tank Size:||N/A|
Java Moss Origins
Java Moss originates from freshwater rivers and streams in Southeast Asia and has been a staple in the freshwater aquarium hobby for many years. It mainly grows on and around the river bank as well as on rocks, both in and out of the water. Java Moss can also be found growing on tree trunks.
Java Moss in the Aquarium
Java Moss is loved by fish breeders, shrimp keepers, and aquascapers alike.
Fish breeders have used Java Moss for many years due to its ability to hide baby fish from larger fish in the aquarium who would happily eat the babies. There are also a number of species of fish who deposit their eggs in or on Java Moss.
Shrimp keepers and breeders also find that Java Moss provides the perfect nursery for baby shrimp. The moss provides cover from fish who may wish to eat the baby shrimp, but also a place where tiny pieces of uneaten food gather, creating a safe haven where the shrimp can grow.
For aquascapers, Java Moss is a wonder plant that can be tied or fixed to rocks and pieces of wood, giving them an aged appearance. World-famous aquascapers like Takashi Amano and George Farmer use Java Moss to bring their aquascapes to life.
Java Moss could not be easier to grow. It is often said that it is near impossible to kill Java Moss.
When placed in the aquarium, Java Moss will sit as a free-form clump on the substrate. It does not put down any roots and can easily be moved by larger fish or the fishkeeper. Given enough time, Java Moss will eventually attach itself to rocks, wood, and even the aquarium glass using rhizoids, (which are short, thin filaments). In my own fish room, I have a 40-gallon tank where the Java Moss has attached itself all along the back wall of the aquarium.
As mentioned above, Java Moss does not grow any roots. Whereas the majority of aquatic plants absorb nutrients through their roots, Java Moss absorbs everything it needs to survive and grow through its leaves.
Using Java Moss in Aquascaping
In recent years there has been a surge in the number of fishkeepers who have turned aquascapers. Largely due to the rise in aquascaping YouTubers, millions of fishkeepers around the globe now take a serious interest in aquatic plants and creating aquascapes.
Being one of the most versatile plants in the hobby, Java Moss finds its way into many, many of these aquascapes. Some use Java Moss as a way to soften the sharp edges of wood, rocks, and other decorations within their display. Others attached it to specifically shaped pieces of wood to create what looks like miniature trees in the aquarium.
Takashi Amano famously used Java Moss to create the effect of bushes in a truly stunning aquascape (see below).
Java Moss Care & Requirements
Java Moss is very undemanding. It is incredibly hardy and will cope with pretty much any water parameters you throw at it. In my own fish room, I keep Java Moss in a tank with Fancy Goldfish, who are kept at around 64°F (18°C) as well as in my Discus tanks which are closer to 86°F (30°C) and pretty much everything in between.
Java Moss is not fussy about water temperature, pH, light levels, CO2, or pretty much any other water parameter you care to measure.
Whilst Java Moss will grow in a wide range of water temperatures, it should be noted that growth slows considerably once the temperature goes much higher than 78°F (25.5°C), with optimum growth being achieved when the water is around 74°F (23°C).
As with temperature, Java Moss will happily grow under almost any light conditions it is provided with. I have even grown it in tanks that were lit by 20W CFL bulbs.
Generally speaking, the less light Java Moss receives, the darker and more straggly it will grow. The more light it receives the brighter and more compact the moss will stay. Whilst I feel Java Moss looks at its best when grown under high light conditions, the more light it receives, the greater the chances algae will begin to grow on the moss, potentially taking over and killing it.
In my experience, the Fluval Aquasky light gets the balance right between the Java Moss looking at its best without becoming an algae-covered mess.
Whatever light you use to grow your Java Moss, consider adding a timer to control the day length of the light. All aquatic plants do better when they receive the same amount of light day after day. Fitting a timer also reduces the chances of the light not getting switched off, which can lead to an algae bloom.
CO2 and Fertilizer
Over the years I have found neither CO2 nor fertilizer makes any real difference to the way Java Moss grows or looks. If Java Moss were the only plant I had in a tank, I would not waste my time or money adding either CO2 or fertilizer.
Java Moss Trimming
Trimming Java Moss could not be simpler. If you have a well-manicured aquascape and you might want to keep your Java Moss under control using a sharp pair of scissors to trim the moss back required. If however like myself you mainly use Java Moss in breeding tanks, then clumps can be pulled off as required and moved to other tanks or sold to other hobbyists.
Unlike other plants, there is almost no way to kill Java Moss by bad trimming. Given enough time, a single strand of Java Moss will grow back to form a thick clump.
One important point to remember is if you are using Java Moss in a breeding tank and you plan to move some of the Java Moss to another tank, make sure there are no fish eggs or baby fish in the clump you move. I once ended up with some Peppered Corydoras in with my Swordtails, and the only way they could have got there was because of eggs being in the moss when I moved it.
Creating Java Moss Trees
One way of growing Java Moss that is taking the aquascaping world by storm is by the creation of underwater trees. When applied to the right piece of aquarium driftwood, the moss creates an effect like a canopy, making the piece of wood look like a tree growing out of the substrate.
The process of creating a Java Moss tree is relatively simple. To start off, find a piece of driftwood that resembles a tree. It is surprising how often the pieces your local store has for sale look like a small tree when you turn them round and round to find the correct angle.
Once you have selected your piece, start by making sure it sinks. Sometimes driftwood floats, and you don’t want to spend hours creating the perfect Java Moss tree only to find the driftwood floats to the surface.
The next step to creating the perfect Java Moss tree is attaching the Java Moss. There are two different ways to attach the moss to the driftwood.
Firstly, the moss can be tied to each branch using some fishing line. Clumps of Java Moss are put in place before being tied by wrapping a small piece of fishing line around the moss and the branch. This method looks unsightly at first, but the moss will soon grow to cover the fishing line.
The second method to attach the Java Moss to the branches is using Super Glue gel (I have used this one from Amazon many times). To glue the moss in place, take a small clump of moss and gently dab it on a piece of paper towel to remove the excess moisture. Next, place a small drop of Super Glue gel where you want the moss to sit, then carefully place the moss on the glue. Hopefully, the moss will hold in place.
Over the years I have used both methods, and the Super Glue method works best for me.
Java Moss Carpets and Walls
Another use for Java Moss that is incredibly popular at the moment is making Java Moss walls or carpets.
Whether you want to make a wall or a carpet, the method is essentially the same. You take a piece of stainless steel wire mesh (size depends on your aquarium) and attached a clump of Java Moss to it using a piece of fishing line. The moss-covered mesh is then laid down in the aquarium and over time the moss grows to completely hide the mesh.
When I make Java Moss carpets I tend to use 4″ (10cm) square pieces of mesh, then lay them out to cover the aquarium floor. With a Java Moss wall, you will typically want one or two pieces of mesh that are large enough to cover the whole area you want to be a moss wall.
As the Java Moss grows simply keep it trimmed and under control. The moss will grow surprisingly quickly, and within a few weeks, the mesh will be completely hidden by moss.
One point to note on Java Moss walls. As the moss at the top of the wall grows, it can shade out the moss growing below it, meaning you have a thick bush of Java Moss at the top of your wall, and bare mesh at the bottom. To get around this problem, try and build your moss wall so you can rotate it every few weeks. I have found that by turning the moss wall 90° once a month the whole wall grows thick and lush without any bare patches.
Java Moss Problems
Whilst Java Moss is incredibly easy to grow, it is not without its potential problems.
One problem Java Moss growers can face is excess growth. Left unchecked Java Moss will continue to grow until it literally fills the entire tank. Now, this isn’t a major problem, because you can just reach into your tank, pull great clumps of Java Moss out, and restore the balance back to your aquarium.
The moss you remove can easily be given away, sold to your local fish store, or just placed on your compost pile.
The real problem with Java Moss is algae. If Java Moss is growing under lights that are too bright, algae can start to grow, and quickly take over your Java Moss. The moss is quickly smothered by algae and may not survive. Equally, once Black Beard Algae or Hair Algae start growing into the clump of Java Moss, you will never get rid of it. Algae-eating fish will help keep it at bay, but you will probably not be able to remove it all.
If you find algae has started to grow in your Java Moss, I would recommend trimming out that section of moss and disposing of it. The rest of your moss will soon grow back.
Selling Java Moss
I often preach the benefits of breeding fish and selling them for a profit, but growing and selling Java Moss can also be extremely profitable.
There are essentially 3 different ways to sell Java Moss. In my experience, all work well, but the amount of work involved in each does vary.
The lowest amount of work is to grab some large clumps of Java Moss from your tanks, chuck them in a bucket and sell it to your local fish store. Any half-decent fish store will sell so much Java Moss they will be more than happy to buy yours from you. I take a 5-gallon bucket of Java Moss in my local store every couple of months and trade it for store credit.
For a little more effort you can sell individual clumps of Java Moss on auction and sales sites like eBay and Craigs List. Selling clumps to other hobbyists is more profitable than selling a bucket to your local store. Typically a portion of Java Moss will sell for between $2 and $15 a portion. Not bad for something you might otherwise give away.
The third and most profitable way to grow Java Moss is attached to mesh for carpets and walls. It takes a bit of time to set up some panels and get the moss growing, and of course, you have to invest in some mesh, but well-established Java Moss mesh panels can sell you $30 or more a panel.
Java Moss is extremely easy to grow and is one of the most versatile plants in the hobby. Whether you hope to create a well-manicured aquascape, or you need a plant for your breeding tanks, Java Moss is probably the plant you want.
With a little care and attention, Java Moss can be kept growing forever. I first purchased a small piece around 15 years ago, and I now have it in dozens of the tanks in my fish room. I wouldn’t want to be without it.