Bacopa Caroliniana, known as Mint Bacopa, Lemon Bacopa, or Blue Waterhyssop, is one of the most popular and easily obtained plants in the aquarium hobby. Its reputation as an old standby is well-deserved, as it is quite undemanding. Its bold leaf structure and relatively slow-growth pattern make it a popular choice in aquascaping. It can be shaped at the discretion of the aquarist. Coloration is generally greenish-yellow, but under intense light or in the upper portions of the aquarium, growing shoots will often gain a pinkish or copper-brown color.
As with most plants, coloration is improved with regular iron and micronutrient dosing. CO2and macronutrient supplementation will result in slightly faster growth, and leaves will be markedly thicker and larger. When cut or crushed, the plant produces a strong lemon-mint smell. Bacopa Caroliniana can also be kept in outdoor ponds or tubs. When allowed to grow in an emersed state, it will produce characteristic small purple flowers.