Java moss is one of the easiest aquarium plants you can grow. Tropica calls it a hardy plant that makes few demands on the water or light, and rates it easy with a low demand for light and CO2. It attaches to rock and wood and can be pruned to shape.
Naming
Java moss is Taxiphyllum barbieri, and it is often still sold as Vesicularia dubyana. The older name has stuck in the trade long after the classification moved on, so both point at the same plant on a shop shelf.
Attaching and shaping it
| Requirement | Java moss |
|---|---|
| Light demand | Low |
| CO2 demand | Low |
| Difficulty | Easy |
| Growth rate | Medium |
| Placement | Attach to rock or wood |
Tie a thin layer onto the surface you want it to cover rather than piling it on. A thick clump shades its own base, and the buried portion browns off while the top grows. Spread it thin, secure it with thread or gel glue, and let it knit in.
Trimming is what keeps it looking deliberate rather than shaggy. It takes a trim well and regrows from what you leave behind, which is how people get the neat mossed branches and moss walls you see in Nature Aquarium layouts. Spider wood is a natural host for it, and so is the pitted surface of Ohko stone.
Java moss or Christmas moss
Christmas moss, Vesicularia montagnei, is the other moss you will meet. Its side branches look like fir tree branches, which is where the name comes from. Tropica calls it more demanding than ordinary Java moss and slower growing, and rates it medium difficulty with a medium light demand, although its CO2 demand is still low.
Java moss is the better first moss. Christmas moss is the better-looking one once you can keep it.
Java moss questions
How do you attach Java moss to wood or rock?
Spread a thin layer over the surface and hold it in place with cotton thread, fishing line or gel glue. Tropica suggests fishing line or cotton thread to hold it until it has gained a hold.
Why is my Java moss turning brown underneath?
Usually because the layer is too thick. The top shades the bottom, and the lower portion dies off. Thin it out and trim the top regularly so light reaches through.
Does Java moss need CO2?
No. Tropica rates its CO2 demand as low, which is a large part of why it is a common first moss.
Sources: Tropica, Taxiphyllum barbieri 'Bogor Moss'; Tropica, Vesicularia montagnei 'Christmas Moss'; Flowgrow, Taxiphyllum barbieri (Java moss).