Is this normal cory breathing?

[sparky_the_fish]

I've noticed that my corys have very rapid movement at what i think is the front of their gills (so near the mouth). I'm not sure what I'm seeing. Is this rapid breathing or something else or normal?

The two corys are in a 120 litre tank with a small clown plec, two danios and two otos. The tank was cycled well before the corys arrived. Current test readings are zero ammonia, zero nitrite and about 20/30 nitrate (same as local tap water). Temp is 25 degrees C. I do a 25% or larger water change once a week.

The danios do not show this behaviour, the plec is normally hiding so I'm not sure about him but I think that the oto may be doing the same. Otherwise the fish seem happy and healthy - they look nourished and have no spots or marks.

I have two other corys still in my quarantine tank that I got from the same shop but about two months later. They have the same rapid movement near their gills.

Any advice from other cory owners will be much appreciated please :help:

 

[MySpace Mike]

corys have rapid movement period. they are a small hyper active fish. my corys do the same things, looks like theyre breathing heavily all the time.

 

[Carp37]

Mine vary- they especially look like they're breathing rapidly when they're chewing. If they're not making a LOT of trips to the surface for air and not flashing on gravel/rocks they're probably OK.

 

[sparky_the_fish]

Thanks for your replies. Sounds like my fish are behaving normally for corys - which is a big relief