Water hyssop, also sold as moneywort or dwarf bacopa, is a tough stem plant with small, thick, oval leaves arranged in pairs up the stem. Grown out of water, it produces small white to pale pink flowers.
Bacopa monnieri is slower and smaller than the Bacopa caroliniana that many keepers know. It is a good beginner stem plant for low to medium light.
Origin
The species grows in wetlands throughout the tropics and subtropics, including the southern United States, India and Southeast Asia. It is also a well-known herb in traditional Indian medicine.
Appearance and growth
Stems grow upright and reach the surface in time, with leaves about 1–2 cm long. Growth is slow to moderate. Under strong light, the tips take on a slight bronze tint.
Placement
Plant it in groups of five or more stems in the midground or background. Space the stems a little so light reaches the lower leaves.
Light, CO2 and nutrients
Low to medium light is enough. CO2 and a liquid fertiliser speed up growth and keep the leaves dense, but neither is essential.
Water conditions
- Temperature: 18–30°C
- pH: 6.0–8.0
- Hardness: 3–15 dGH
It tolerates slightly brackish water, which makes it useful in brackish tanks too.
Propagation and maintenance
Cut the top few centimetres off a stem and replant it. The lower stem will branch from the cut. See how to trim stem plants.
Compatibility
Its tough leaves are rarely eaten, so it works with most community fish, many cichlids and goldfish. It is also good for shrimp tanks.
Common problems
Lower leaves drop in dim light or when stems are crowded. New stems from emersed farms may shed some leaves as they adjust; this is normal. See how to prevent plant melting.
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