Bacopa salzmannii 'Purple' is a stem plant from tropical America producing small, oval leaves up to 2cm across that turn a deep, rich purple when submerged. The colour is significantly more vivid underwater than in emersed form — anthocyanin production in the leaves intensifies once the plant adapts to aquarium life — providing a striking contrast against the predominantly green plants in most layouts.

It is easy to grow: plant stems in groups in the substrate and trim regularly, replanting the cuttings. Growth is slower than Bacopa monnieri, which is actually an advantage — it holds its shape with less frequent maintenance. CO2 supplementation is not essential but improves both the growth rate and the depth of purple colouration.

Plant in groups in the midground to background. Trim regularly to encourage a bushy, well-structured form.