Water stargrass, Grassleaf mudplantain, Zosterella dubia, Heteranthera graminea
Family
Pontederiaceae (pickerelweed family)
Origin
North and Central America, from Canada to Guatemala
Water
freshwater
Temperature
10–26°C
pH
7–8.5
Hardness
8–20 dGH
Care level
beginner
Lighting
Medium to high light; CO2 not essential
Care
A perennial water plant of rivers and lakes from Canada to Guatemala, most common in alkaline water. It grows from about 5.5 m deep right up to stranded plants on the shore, and its narrow, grass-like leaves vary a lot in size and shape between submerged and land forms. Each flower stem carries a single yellow flower that opens in the morning and wilts by evening. Our sources say little about it in aquariums. It is used as a long-stemmed, grassy background plant, in the same way as its tropical relative Heteranthera zosterifolia. Its wide range into Canada means it suits coldwater tanks and ponds as well as cooler tropical tanks. Water figures are our estimate, not from the sources. The higher pH and hardness reflect its liking for alkaline water. Sources: Wikipedia (en.wikipedia.org/wiki/Heterantheradubia); Wikipedia, List of freshwater aquarium plant species. Checked October 2026.
Breeding
Sets capsules with many winged seeds. In tanks, cuttings are the practical way: replant shoot tips in the substrate.
Compatibility and tank mates
Suits coldwater tanks and ponds as well as cooler tropical tanks. Goldfish may graze the soft leaves.
Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.
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