I currently have a ten gallon aquarium housing a female betta and a
small school of espei rasboras. I was thinking of converting the tank
to a southeast asian swamp biotope (idea from Peter Hiscock
_Aquarium_Designs_).

However, the plants suggested in the book don't necessarily grow in SE
Asia. I am not sure what plants would work, as from my understanding a
biotope is sort of like a snapshot of a specific spot, and SE Asia
covers a rather large area. I'm not even sure the rasboras and betta
would be in the same biotope!