Java moss is among the first plants grown in fish tanks. It is hard to kill, grows reasonably fast, and provides a terrific hiding spot for fry.
For fish breeders, they need the jungle of java moss for juvenile fish to hide amongst it. The big fish are monsters in an aquarium. The parents eat their young. Most fish species are cannibals.
The moss serves a few core functions. It protects fry, provides a habitat for spawn, and the moss is a partial water cleaner. It soaks up ammonia and nitrates helping to keep fish healthy and other plants alive underwater.
Naturally, nothing lasts forever.
When java moss turns brown, it needs to be fixed or replaced. When you need to replace it, the obvious question is how fast does java moss grow? It isn’t just a filler plant, after all. It is part of the ecosystem.
Fry live or die by the health of the java moss.
Under normal conditions, it takes a few weeks for the moss to anchor onto a new substrate. When you need java moss to put on faster growth, specific growing conditions need to be met.
Covered below are what those specifics are to get java moss growing fastest.
How to grow java moss fast
Maintain temperatures between 70 and 75-Fahrenheit. Warmer temp’s slow growth. Add air stones to provide water movement to let the water reach all parts of the plant. Add liquid CO2 and fertilizer after one week, and grow them under low lights to prevent algae growth.
Java moss is adaptable to a range of temperatures. It will still grow in water reaching as high as 86-Fahrenheit. It will be slower though.
To get java moss growing quicker, check the water temperature. Anything above 75-Fahrenheit is too high. Drop the temperature to speed up growth.
2. Add in air stones
Consider the java moss as the underwater dancer. It does not like to sit still. It prefers to wave its leaves around letting the oxygenated air reach every part of the plant.
When air movement is restricted, the growth rate is stunted.
Air stones are the simplest solution to boost circulation.
In aquariums, the water is already oxygenated. That will keep plants alive. Do not mistake pumps for promoting air circulation. Those only oxygenate it.
Java moss attached to driftwood or rocks in a corner of an aquarium can still lack the air circulation required for growth.
When circulation is poor, drop in an air stone or two. The bubbles will get the plants foliage moving around.
Liquid CO2 can be added to the water to bump up the speed of growth. However, java moss grows fairly quickly without it, provided the water is clean of algae.
If you grow in bright light (covered below), algae will be more likely to become a problem. Fertilizer gets used more by plants when they are growing under bright light.
Unfortunately, the trade-off with java moss is algae. The fertilizer would wind up feeding algae rather than the plant introducing more problems than solutions.
4. Lighting requirements to speed up growth
Low to medium light is preferable. They do grow through photosynthesis. Higher light will speed up growth, but that is also going to promote algae growth.
Increasing the light will not speed up the growth rate of java moss. Algae grow faster so that will get nutrients from the water, depleting the moss of the energy it needs to grow.
Light requirements for java moss are nothing special requiring fancy addons to a tank. Java moss grows in all types of light. With moss being adaptable to a range of lighting conditions, this is one plant where LED plants are worth it.
LEDs are sufficient for providing a decent quality of light with a very low amount of heat. They prevent the light from changing the water temperatures too drastically.
Fluorescent lights work too, but LED is sufficient for java moss growth without encouraging any other fungi or algae to grow along with it.
Propagating java moss
Perhaps the simplest way to control the growth cycle of java moss is through propagation.
It only needs water, low light, and a substrate to attach to.
In aquariums, it can quickly grow out of control. The way around too fast a growth rate is to use a moss breeding tank. That can be any size. From a 5-gallon tank and upwards to an empty glass jar from the kitchen.
An anchoring material is all you need to start it growing
Even a piece of driftwood or a decent-sized rock for the rhizoids to attach to will work.
Grow the moss in a sealed glass jar or tub filled with water and use an air stone to boost air circulation underwater.
After a week, add a little liquid CO2 and fertilizer to push the plants’ growth. Drop the lighting levels to prevent algae formation.
Once the java moss is anchored onto the substrate, the propagated java moss can then be dropped into the aquarium and replaced as and when required.
This is the easiest method to grow java fast without risking turning an aquarium into an algae farm.
Grow the java moss separate from the tank under low lights and fertilized, then if things go wrong in the tank, there will be replacements on hand to swap out the damaged moss.
Common problems with growing java moss fast
Java moss turning brown
When java moss does not get the nutrients it needs for growth, it will brown. The first sign of discoloration is the center of a dense clump.
Java moss turning brown from the center is an indication that air circulation is not strong enough.
Either drop in air stones, trim the moss to increase air movement, or replace it with propagated moss.
Java moss clogging filters
Java moss should be anchored to a substrate in an aquarium. It is lightweight so will be drawn towards the filters. When trimming moss in an aquarium, it helps to have a suction tube at-the-ready to remove cuttings from the tank rather than leaving them floating in the water.
Given these can get large, they can block the filters, which is why they should be anchored down.
If you prefer to have floating java moss, the alternative is to place a mesh netting around the filter to keep floating moss at a distance
Frequently Asked Questions related to growing java moss fast
Does fertilizer need to be used to grow moss faster?
Liquid CO2 and fertilizers help to put on a fast burst of growth. It is not suitable in the long term as it will promote the growth of algae. Too many algae clusters deplete essential nutrients java moss needs to have for growth. Only add fertilizer sparingly, and only when growth is stunted.
Does java moss grow faster at the top of the tank or the base?
The stronger the light, the faster java moss grows. Grown at the top of a tank, it will grow faster. Under bright light, algae will be more likely to form, too. For fast growth, the top of the tank grows fastest but will need more maintenance to prevent algae from taking over.
Marcel runs the place around here. He has a deep passion for houseplants & gardening and is constantly on the lookout for yet another special plant to add to his arsenal of houseplants, succulents & cacti.
Marcel is also the founder of Iseli International Commerce, a sole proprietorship company that publishes a variety of websites and online magazines.