Java Moss is a popular, useful and versatile moss which comes from Asia, Malaysia, Java, and India. It can grow on nearly any surface or free floating. It is classified in the Hypnaceae family which consists of ‘sleeper mosses’ which typically exhibit creeping growth. It has tiny lanceolate light to medium green leaves 2-4 mm long in two rows on either side of a slender stem. In the emersed form, leaves are wider and glossy dark green to olive yellow-green. It can be initially secured to a rock, root, bark, etc. And its rhizoids will adhere and grow by means of a large number of red-brown root like threads. Heavily branched shoots quickly create a thick cushion which can be thinned and/or cut back as wished. It can be grown near the surface and, in nature, is usually found above water growing up tree trunks, around stones or on the ground in moist jungles. For this reason, it is ideal for paladariums
It propagates by division of side roots. Red-brown sporocarps (blooms) are formed both above and below the water in moderate to low lighting. It is distinguished from Glossadelphus zollingeri in that it never forms sporocarps underwater. It is quite accommodating in that it grows in a PH of 5.8-7.5 and from 18-30 degrees Celsius. It likes soft clear water. Debris from the tank may accumulate among its threads. This should be rinsed out as should any build-up of algae, as both will hinder its survival and growth. Strong light tends to only cause algae to grow on the moss rather than promote growth of the moss. Nourishment is derived entirely from the water in which it is kept. Java moss is widely used by aquarists as a spawning substrate. The egg scatterers such as rosy barbs will spawn over it and are unable to devour their eggs later as they fall into the moss. Some species of cory cats may spawn in the moss (this makes it very convenient for the keeper to remove the moss and eggs to incubate elsewhere). It is also an excellent media on which to hatch eggs such as Australian rainbows and will facilitate the production of infusoria for such tiny fry. It is also useful as dense cover for an ‘estranged’ mate following spawning (e.g. dwarf gouramis, bettas, etc.). It is quite coarse and I have not encountered any fish with a taste for it (excluding of course large cichlids!).
By Twyla Lindstrom-Peters
From “Fins & Friends” Regina Aquarium Society, Canada