- Scientific name: Bacopa caroliniana
- Synonym: Bacopa amplexicaulis; Monniera crenata; Hydrotrida caroliniana
- Common name: Giant bacopa
- Family: Scrophuladaceae
- Group: Aquarium plants
- Max height: 60 cm
- Distribution: North America; Southern and middle U.S., Central America
- Habitat: Grows in marshy areas, at the edges of small streams, sometimes submersed in shallow water, but usually semiaquatic.
- Substrate: Plain gravel
- Placement in aquarium: Background, middleground
- Planting density: 4-5 plants for 20 cm2
- Lighting needs: Bright
- Temperature: 24-26°C
- pH: 6,5-7,5
- Hardness: 3-6 NK°
Description: Given good lighting, a fine substrate and regular fertilization, this plant will prove a highly adaptable and hardy variety, ideal for most aquariums. It does better in clean, clear water. The small (2,5 cm) light green, oval leaves contrast well with other leaf shapes. Plant giant bacopa in groups, roughly in 3-5 cm apart.
Although Bacopa caroliniana belongs to the light-requiring species, it is otherwise undemanding. It grows in both unheated room aquariums or paludariums as well as in tropical aquariums up to 25 °C. It can handle higher temperatures only temporarily. Pure sand, to which a little loam can be added, will suffice as substrate. The species will display better growth in soft rather than hard water. To achieve a good visual appearance, Bacopa caroliniana should be arranged in a terrace in the foreground or in the middle section of the aquarium. During summer, emersed cultivation on the edges of ponds in which case flowers will often develop poses no difficulties either.