Bolbitis heudelotii, the African Water Fern or Congo Fern, is a beautiful, slow-growing aquatic fern from the family Lomariopsidaceae native to tropical and subtropical Africa, particularly the Congo River basin and surrounding regions where it grows submerged or partially submerged in fast-flowing, clear, highly oxygenated, soft and slightly acidic water over rocky substrates. In the aquarium it is considered one of the most spectacular of all epiphytic ferns, producing large, compound fronds of 20–40 cm with deeply pinnate, irregularly lobed leaflets. The fronds have a unique semi-translucent, dark green to blackish-green color and a somewhat glossy texture that appears dramatically different from the opaque, solid green of Java Fern. When positioned in the current from a powerhead or strong filter, the large fronds wave gracefully in the flow, creating an extraordinarily natural, river-like effect. Bolbitis is grown as an epiphyte — attached to driftwood, rocks, or hardscape by its thick, dark rhizome, with roots gripping the surface and fronds extending upward and outward into the water column. Unlike Java Fern and Anubias, Bolbitis is more demanding: it requires clean, well-oxygenated, soft, slightly acidic water and does not tolerate stagnant conditions, high nitrates, or alkaline hard water well. CO2 supplementation significantly enhances growth, and high water flow is actively beneficial rather than merely tolerated. This species is the centerpiece of many West African biotope aquariums, paired with Anubias hastifolia, Congo Tetras, and West African cichlids.
