Panda Cory strange behavior?

[MMac]

Hello,

One of my about 15 panda corys is constantly swimming to the top of the water line and looks like she is gulping air. It is the same one all the time - I know this b/c she is the biggest and most white in color. It seems like she does this almost constantly throughout the day. She is probably between 2 and 3 years old. She eats and scrounges around like the rest at meal time and will rest from doing this throughout the day. She doesn't see to be laboring in breathing.

My set up is as follows.

50 gal tank 48x18x14
1 fluval 307 canister filter
1 aquaclear 30 hob filter
co2 injection is consistent and indicator turns light green about 1/2 way through the day
lights on 6 hours/day
plenty of surface agitation

change water 1x week at @ 30%

water parameters stable - same each week

0 ammonia
0 nitrites
~5-10 nitrates
~6.6 ph
~150 TDS

I use RO water for water changes and top offs during the week; at wc I add about 1/2 cup per gal of tap to remineralize and use seachem prime to neutralize the chlorine

tested RO water with today's wc
0 ammonia
0 nitrites
0 nitrates
16 TDS
6.0 ph

i use trickle add method on wc

my stock is
~15 panda corys
3 corydoras
9 ember tetras
1 assassin snail
pond snails
3 amano shrimp
lots of neocardina shrimp - ugh - sold these instead of amano and boy to the procreate.

Any thoughts? Not an issue? Getting old?

 

[DoubleDutch]

After feeding mainly ?

 

[MMac]

After feeding mainly ?

No. I feed early morning before lights on and only once a day. She does it off and on through out the day, spending blocks of time doing it.

Also, sorry, I think I reposted this again. I will find and delete the second one if I can figure it out.

 

[JJun]

After feeding mainly ?

I've been doing alot of research on the Panda Cory because that is the next fish I will be getting for my tank. I have read many post saying that it is normal for them to go up to the top of the tank. Also saw some posts that said they are able to get oxygen form air when needed. But it does seem like a normal activity for them...

 

[MMac]

I've been doing alot of research on the Panda Cory because that is the next fish I will be getting for my tank. I have read many post saying that it is normal for them to go up to the top of the tank. Also saw some posts that said they are able to get oxygen form air when needed. But it does seem like a normal activity for them...

Yes, the can and do, but it seems she does it excessively. None of my other pandas do this. They happily search the sand all day long for any leftover scraps all day long. She does this too, but I find that she also spends an inordinate amount of time swimming to the top. She has been doing it for a while now, so perhaps it is just who she is. ??? You will enjoy the pandas if you get them. They are happy little scavengers!