African water fern
Bolbitis heudelotii
Also known asAfrican water fern · Congo fern · Creeping fern
Water parameters
Light and nutrients
Substrate type: epiphyte. Propagation: rhizome division.
Substrate compatibility
| Substrate | pH effect | Nutrient load |
|---|---|---|
| Wood and rock mounts (Hardscape mount) | varies | none |
| Inert sand (Pool filter sand) | neutral / inert | none |
| Inert gravel (Aquarium gravel) | neutral / inert | none |
| Bare bottom (no substrate) (Bare bottom) | n/a | none |
| Aquasoil (ADA Amazonia) | lowers pH | very high |
| Mineralized clay substrate (Seachem Fluorite) | neutral / inert | moderate |
With fish
Origin and habitat
A true aquatic fern of the family Dryopteridaceae, native across tropical and southern Africa, from Ethiopia west to Senegal and south to northern South Africa, far wider than its 'Congo fern' name suggests. It grows submerged in clean, fast forest streams and rivers over sand or rock, gripping rocks and wood with thread-like rootlets from a creeping rhizome. The dark-green, finely divided pinnate fronds reach 15–40 cm long and up to about 25 cm broad, giving a lacy, translucent texture, and the plant is a rheophyte built for current. It is among the most refined-looking aquarium plants when grown well.
Care notes
Attach the rhizome to driftwood or rock with thread, glue or fishing line, and never bury it in the substrate, which rots it just as with Anubias and Java fern. Keep light low to moderate, about six to eight hours a day; bright light mainly feeds algae on the delicate fronds. Growth is genuinely slow, on the order of one or two new fronds a month even in good conditions, with visible spread measured in months not weeks. CO2 is not required but speeds growth and produces larger, more finely cut fronds. Good flow matters: the fern comes from fast water and does best near a filter outlet, where current carries nutrients across the leaves and keeps detritus from settling in the fine divisions. Water should be soft to moderately hard and slightly acidic to neutral, and temperature around 20–27°C. Propagate by splitting the horizontal rhizome into sections with two or three leaves each; some fronds also form plantlets at the tips, like Java fern. Black or browning leaves usually mean too much light without CO2, unstable parameters or sediment on the fronds, so trim them at the base and check conditions. It pairs naturally with Anubias, Java fern and Bucephalandra on wood for an African biotope look, the dark lacy fronds contrasting against lighter plants and pale substrate. It is an ornamental epiphyte, not a crop, so it is unsuited to media-bed aquaponics or hydroponics.