Java Moss, of the Hypnacae family, makes for a great addition to the aquarium; easy it is to grow, how hardy it is, and the tank health improvements offered.
Amongst one of the fastest growing and hardiest types of aquarium moss around, Java Moss is a very popular choice for tanks thanks in large part to how easy it is to care for, as well as the benefits that it can provide. Also known by its Latin name of Taxphyllum Barbieri, the moss tends to grow into large clumps that can make for a great lining for the bottom of the tank, or it can be attached to driftwood or stone. Thanks to its fast growth, it's also commonly used to cover up gaps in aquascapes.
Southeast Asian in origin, this bright and thick moss makes for an excellent part of any rainforest or jungle aquascape in your tank. Naturally, it grows on rocks, river banks, and even tree trunks in moist tropical climates. It doesn't require much in the way of either water quality of lighting, which makes it a highly versatile and commonly used moss. While it looks somewhat like Christmas Moss or Peacock Moss, it does not grow as compact as them, spreading out much more quickly than either.
Aside from aquascaping your tank, java moss also offers some benefits towards the quality of life for fish in the tank. Its thick, carpeting appearance offers great coverage for eggs, fry, shrimp, and small fishes. If used for this type of coverage, it's usually recommended that you use several clumps rather than one.