American frogbit, American spongeplant, Hydrocharis spongia
Family
Hydrocharitaceae (frogbit family)
Origin
Central and south-eastern USA, from the Lower Mississippi Valley to the coastal plain from Texas to Delaware
Water
freshwater
Maximum size
50 cm
Temperature
10–28°C
pH
6–7.5
Hardness
2–15 dGH
Care level
beginner
Lighting
Medium light; CO2 not needed
Flow
Gentle; dislikes strong surface flow
Care
American frogbit is a floating or emergent plant of slow and stagnant water in streams, bayous, swamps and ditches in the south-eastern USA. It has heart-shaped to round leaves 2–7 cm across: floating leaves have red-tinged spongy tissue underneath, while leaves raised above the water lack it. Plants can reach about 50 cm long. It is used to shade fish in tanks and ponds. Grow it like Amazon frogbit, which is smaller and more often sold. It can be confused with water hyacinth, but has whitish roots and ridged leaf stalks. In the wild it can form dense mats that use up oxygen. Water figures are our estimate, not from the sources. It suits large tanks, ponds and warm-temperate conditions better than small aquariums. Sources: Wikipedia (en.wikipedia.org/wiki/Limnobiumspongia); Wikipedia, List of freshwater aquarium plant species. Checked October 2026.
Breeding
Spreads by runners that produce new rosettes. Plants are mostly male or female, and flowers form mainly on emergent plants.
Compatibility and tank mates
Floating plant: good cover for bettas, gouramis, killifish and fry, and the roots shelter shrimp. Goldfish, koi, silver dollars and many herbivorous fish eat it. Keep surface flow gentle and leave open water so labyrinth fish can reach the surface.
Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.
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