Bacopa serpyllifolia is a South American species new to the North American aquarium hobby. Like similar species, it inhabits the margins of drying pools, growing submerged in the rainy season and flowering as the water recedes. Sold as Bacopa sp. ‘Japan’, it likely acquired that trade name merely by being imported from or popularized there. There are apparently not even any Bacopaspecies native to that country, and those of the Asian mainland are distinctly dissimilar. At present, it is only available in the United States through trade with other hobbyists.
Bacopa serpyllifolia will undoubtedly find widespread application in aquascapes. Unlike most other known Bacopas which grow in a strictly vertical fashion, this species grows in a mostly prostrate manner. It will gradually gain more height than might be desired, but with selective pruning, can easily be made into a contoured mid ground bush. Its small size and vibrant, lime green color make it especially suited for such a role.
For successful culture, strong illumination is indispensable. Also important are relatively large quantities of iron and carbon dioxide. Newly acquired specimens may take quite a while to adapt and start growing, which is not cause for concern. Emersed cultivation should pose no problems provided sufficient light and space are provided.