Disk water hyssop, Round-leafed water hyssop, Moniera rotundifolia, Herpestis rotundifolia
Family
Plantaginaceae (plantain family)
Origin
Central USA
Water
freshwater
Maximum size
30 cm
Temperature
15–28°C
pH
6–7.5
Hardness
2–15 dGH (estimate)
Care level
beginner
Lighting
Medium light; CO2 not needed
Care
Round bacopa or disk water hyssop is an aquatic Bacopa from waters of the central United States, with round leaves 1–3 cm wide, each with six veins running lengthwise, and white flowers with yellow throats in autumn. Wikipedia gives no aquarium details. It is grown as an easy, light-green stem plant for the midground. Water figures are our estimate, not from the sources. As a central US native it tolerates cooler water than most tropical stem plants. Wikipedia says it is an invasive weed of waterways outside its native range. Never release this plant or dispose of it in drains or waterways; it is invasive in some countries. Sources: Wikipedia (en.wikipedia.org/wiki/Bacoparotundifolia); Wikipedia, List of freshwater aquarium plant species. Checked October 2026.
Breeding
Take stem cuttings or side shoots and push them into the substrate; they root quickly.
Compatibility and tank mates
Fairly firm leaves, though goldfish, large cichlids and herbivores may still eat it. Fine with shrimp, snails and community fish.
Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.
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