Java Moss

Java moss is the most widely used moss in the hobby. It has no roots; it clings to rocks, wood and decor with fine rhizoids. It is very hardy, and its light and CO₂ needs are low. In shrimp tanks it is invaluable as a biofilm surface, as a hiding place for shrimplets and the fry of livebearers, and as a spawning medium for egg scatterers.

• Spread it as a thin layer over wood or rock; secure it with cotton thread, fishing line or aquarium-safe gel glue. It attaches within a few weeks.
• For a "moss wall" or "moss carpet", it can be sandwiched between two pieces of mesh.
• Prefer a thin layer to a thick clump: the lower parts do not get light and turn brown.

• Light: low to medium; in strong light it grows denser and more compact but may collect algae.
• CO₂: not required.
• Fertilizer: fish waste is usually enough.
• Trimming: shape it regularly with scissors; remove the cut pieces from the tank, otherwise it spreads everywhere.
• Cleaning: debris builds up inside the moss; rinse it in tank water from time to time.

Every cut piece becomes a new plant: simply tie the trimmed moss to another rock or piece of wood.

• Browning: the underside of a thick clump is not getting light, or the inside of the moss is dirty; thin it out and clean it.
• Algae (green thread) mixed in: too much light and nutrients; reduce the light; Amano shrimp and otocinclus help.
• Very slow growth: the moss slows down at temperatures above 28°C.