Water spangles (Salvinia natans) care guide

Group
Plants
Other names
Floating fern, Floating watermoss, Water butterfly wings, Marsilea natans
Family
Salviniaceae (floating fern family)
Origin
Temperate and warm Europe, Asia and North Africa; introduced in New York and Massachusetts
Water
freshwater
Maximum size
3 cm
Temperature
10–26°C
pH
6–7.5
Hardness
2–15 dGH
Care level
intermediate
Lighting
High light; CO2 not needed
Flow
Gentle; floating plants dislike strong surface flow

Care

Salvinia natans is a floating fern found across central and southern Europe, Asia and North Africa, on sunny, standing water. Each node has two flat floating leaves, roughly the size of a fingernail, with air pockets for buoyancy and water-repellent bumps on top, plus a hanging, root-like submerged leaf. Note that the common name "water spangles" is also used for Salvinia minima. Unlike the tropical species it is an annual: it grows through the warm months, produces spore cases at its base, and the plants die off in autumn, so it does not last indefinitely in an aquarium. It is best suited to an unheated tank or garden pond in bright light, with humid air above the surface. Water figures are our estimate, not from the sources. It can carpet whole ponds and shade out submerged plants where it has been introduced. Never release this plant or dispose of it in drains or waterways; it is invasive in some countries. Sources: Wikipedia (en.wikipedia.org/wiki/Salvinianatans); Wikipedia, List of freshwater aquarium plant species. Checked October 2026.

Breeding

Multiplies vegetatively through the summer as the stem branches and breaks apart. Being an annual, it survives winter as spores: spore cases form at the base of the plant, and new plants appear the next season. In aquaria it is usually replaced each year.

Compatibility and tank mates

Suits coldwater tanks and ponds better than tropical aquaria. Goldfish and koi may graze it; small fish, shrimp and snails leave it alone, and the hanging leaves shelter fry. Avoid strong surface flow.

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

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