Two main genera of fern are available in the hobby: Microsorum and Bolbitis. Most are epiphytes, meaning that they grow on a surface like rocks or wood instead of in the soil.Ferns are non-flowering plants which propagate by microscopic spores. Ferns also propagated partly vegetatively, often producing roots from rhizomes that can attach to rocks or wood ornaments in the aquarium making them easy to be propagated by the aquarist.

Microsorum is a genus of over 50 species of tropical ferns with only a few that can be grown in aquariums (mainly Microsorumpteropus – varietys). Like most ferns, they grow from rhizomes, rather than roots. The genus name is often misspelled "Microsorium" or "Microsoreum".

Bolbitis is a genus of ferns in the subfamily Elaphoglossoideae.Two particular members of the genus are often grown aquariams, B. heudelotii, and B. heteroclita.