Bettas come from
a group of fish called anabantoids. Anabantoids are fish that are able to
breath air from the surface of the water unlike other fish which extract oxygen
from the water as it flows across their gills. Anabantoids tend to live in
small pools where the water is very still, murky,stagnant and low in oxygen
and have evolved to take the oxygen from the surface instead.A suprabranchial
organ is used by anabantoids , gulping in atmospheric air from the surface
of the water the air is then passed to the organ (known commonly as the labyrinth
)This organ is is suffused with capillary beds which extract oxygen from the
air. When your Betta aproaches the surface of the water They exhale before
gulping in air from the surface
