Propagation
Divide rhizomes in to lengths during growing period.  

Place spores on sterilised sphagnum or peat moss then cover with glass, keep moist for 4 to 6 weeks maintaining a temperature of 16º C (61º F), with indirect light. 
Cleanliness is essential during the propagation process.

Botanic information
Leaf: The dark green pinnate fronds have 4-wedged-shaped pinnae that are arranged in opposite pairs and are rounded or notched on the outer edge giving it an orbicular-like appearance. The petiole is up to 300mm (1 ft) long.

Flower: The spores are produced in a sporocarp that is attached to the rhizome at the base of the petiole. This unusual fern produces micro and macro spores that form male and female prothallus. They appear during summer.

Fruit: This plant is normally reproduced vegetatively from rhizomes.

The spores are produced in solitary hard sporocarps and mounted on a long unbranched peduncle. The fruit was commonly collected by the Australian Aboriginals as a source of food. 

Note
A canopy of leaves (pinnae) covers the rhizomes forming a low clump and at night the leaves tend to fold up and the upright rhizomes that become terrestrial during periods of low water.

The leaves are glabrous when floating and pubescent when grown terrestrially with a petiole that can be up to 300mm (1ft) long depending on the depth of the water. The Australian aboriginals collected the pea size sporocarps and ground it in to a paste for consumption but improper preparation can be fatal and kill several unaware early European explorers.