Two-leaf water fern (Regnellidium diphyllum) care guide

Group
Plants
Family
Marsileaceae (water-clover family; a fern)
Origin
South-eastern Brazil and neighbouring Argentina
Water
freshwater
Temperature
18–28°C
pH
6–7.5
Care level
intermediate
Lighting
Medium to high light; CO2 helpful

Care

The two-leaf water fern is the only living species of its genus, a small aquatic fern from south-eastern Brazil and Argentina. It looks like a water clover (Marsilea), but each leaf has two rounded lobes instead of four. Wikipedia notes that it is sometimes grown in aquaria. Like Marsilea it creeps along the substrate on a thin rhizome, making a low cover in the foreground, or it can be grown emersed in paludariums and shallow tubs, where leaves stand taller. Give it a fine, nutrient-rich substrate and good light. Water figures are our estimate, not from the sources. Sources: Wikipedia (en.wikipedia.org/wiki/Regnellidium); Wikipedia, List of freshwater aquarium plant species. Checked October 2026.

Breeding

Cut the creeping rhizome into sections with leaves and roots and replant them. It also forms spore cases (sporocarps).

Compatibility and tank mates

Digging fish may uproot the creeping rhizome. Suits shrimp and small community fish.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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