Why do Cory's do this ?

[rvijay07]

Sometimes, Cory's come very fast from the bottom to the top, strike the surface and then return back down. It appears almost as if they are trying to jump out ? I wondered about this for a long time. Why do Cory's do this ?

Vijay :?

 

[e-cat]

the breath the air as well as useing there gills for breathing underwater.

 

[rvijay07]

Does this mean that my tank water has lesser dissolved oxygen ?!!

Vijay :?

 

[e-cat]

nope, they will do it no matter what, it doesnt water how my power heads, air stones or whats you have in your tank too airate the water they will continue too did it. it doesnt mean theres any thing wrong with your tank or your fish.

 

[TankGirl]

They are a labyrinth fish, who gulp air and obtain the oxygen in their stomachs. I think is a cool behavior, but it does seem bizarre!

 

[madasafish]

I belive cories are able to breath air, but I don't believe they are labyrinth fish (Anabantoids). I think they lack the "labyrinth organ" that bettas, gouramis and snakeheads possess. Let's see if I can prove that...

http://edis.ifas.ufl.edu/BODY_FA054 seems to support my claim.

http://talesfromthebackyard.claremc.co.uk/tropicalfish3.html also places them in a separate category.

However, the ability to breath air in either of these ways is clearly an adaptation that helps fish deal with water in which there is little oxygen. It's also the kind of adaptation that led our ancestors to crawl out onto land. (20% of the gas in the air we breath is oxygen. In water, less than 1 part per hundred is oxygen).