Hi Louis,
We have several samples of Barbula which we are growing emerged in high humidity on bog wood pieces .
Tropica supplied us with these "rarities" and we have it from them that this species can be grown immersed.
It is a very intense green in colour with a beautiful compact growth pattern, it is certainly growing on us.
It does not feature on our website as we treat it as an in store surprise but PM or phone if you are interested.
Best regards,
Mark and Jim.