Pogostemon helferi (TC)
This species of Pogostemon has a wavy leaf once mature. Submersed, the stems can grow fairly long, while emersed growth tends to be much more compact.
Difficulty: Medium to Hard. The leaves are a bit delicate and can melt or crisp up easily.
If growing submersed be sure to give plenty of light and gas exchange. CO2 is not required but will help with growth. Iron supplements will help to enhance a red coloration but are also not required.
If growing emersed be patient with acclimating the plant to ambient humidity. The leaves will acclimate fine if slowly introduced but will dry if done too quicly. Even if some leaves are lost the stem is typically still intact and will grow new ones! If growing the in the path of water or a mist system, the plant can be added immediately with no acclimation period.