Crepidomanes malabaricum

Crepidomanes malabaricum is a filmy fern belonging to the family Hymenophyllaceae, characterised by fronds that are only one cell layer thick — giving the plant an extraordinary translucent, almost ghostly appearance under backlight. It forms dense, lush cushions or spreading mats of tiny, intricately divided fronds of deep green, growing on shaded, moisture-laden rocks and wood in tropical forest streams. This is among the most delicate and beautiful aquatic plants available for specialised setups.

In the aquarium, filmy ferns like Crepidomanes require very specific conditions: shaded, humid, low-flow environments with very soft, clean water. They are extremely sensitive to algae, strong flow, and water quality fluctuations. This plant is typically more suited to paludariums, humid terrariums, or extremely stable, shaded aquatic setups than conventional planted tanks. For the specialist willing to provide ideal conditions, it is one of the most rewarding and visually spectacular plants in the hobby.

Light: Very low; Crepidomanes is a deep-shade plant and must be protected from any direct or intense light. CO2: Not required; the ultra-thin fronds are sensitive to CO2 fluctuations; ambient aquarium CO2 is sufficient. Fertilisation: Minimal to none; the plant absorbs nutrients directly through its single-cell-layer fronds; avoid over-fertilising. Placement: Attach to shaded driftwood or rock surfaces in areas of very gentle or no flow; humid terrarium setups preferred. Propagation: Carefully peel small sections of the mat from the substrate and re-attach to new shaded hardscape surfaces.