Dont Know If An Emergency But Havent Seen This Before

heya.
 
bought 4 panda corys the other day to bring my total to 7 and they have been getting along great. however yesterday i noticed a small swelling on the belly of four of them (which only appears in 2 today) and im not sure what is causing this as i havent ever seen if before. the swelling is a small, raised, grey colour right between the pectoral fins on the belly. initially i thought it was some sort of bloating in the stomach but im not sure still.
 
the corys werent terribly cooperative with having a picture taken but i got a couple of shots where you can see the swelling on the underside as described.
 
any advice as to what these are and what is causing it would be appreciated!
 

The fact you noticed on 4 of them and only 2 now suggests to me it just full bellies, they are greedy little guys. Not sure how mature these fish are but females tend to be a bit chubbier anyway.

mm ok i thought there was a chance of overfeeding tbh as they dont seem to stop when there is food around. i havent fed them in 40 odd hours so i was starting to attribute the reduced swelling to that. thing is the two who are still swollen havent showed any decrease in the amount of swelling. should i just leave it another day? finally, im right in thinking that's where the stomach is yes?
 
thanks!
 
edit: not sure how old but they are only about 1 inch long (minus dorsal fin) so certainly quite young

Much the same as mine who are little fatties too most of the time. Hopefully it is just natural greed that has caused it. I've been reading up on whether fish overeat, some say yes, some no. BTW its Caudal fin that is the tail, if thats what you meant.

This is 5 of my 6 sterbais taken 2-3 weeks ago there a little bigger now.

Munroco said:

Much the same as mine who are little fatties too most of the time. Hopefully it is just natural greed that has caused it. I've been reading up on whether fish overeat, some say yes, some no. BTW its Caudal fin that is the tail, if thats what you meant.

This is 5 of my 6 sterbais taken 2-3 weeks ago there a little bigger now.

Click to expand...

 
 
they're lovely almost bought sterbais myself but chose panda ultimately. cant wait to get them in my new tank! yes you're right I did mean caudal just had a momentary lapse
 
cheers for the help!

Just a quick mention, any females will develop a larger abdomen when they are adult, even to the point that they will rock back and fore on their bellies like a pendulum when resting on the tank floor, quite comical really. But the ladies do get quite podgy