Do pups nip at each other?

[flukekiller]

I noticed that my pup has a small part of his disk missing. Almost shaped like a 1/2 circle. The other night it was all white and today before work it seems to be healing good. Main question is do pups nibble on each other? My 2 guys are always playing with each other. Funny thing is it is the female that seems to be nibbling on the male. The only other fish are discus.
Ammonia 0
Nitrite 0
Nitrate <5.
It seems to be healing fine and they are both acting normal and eating well. Should I be worried?
Also at what size/age are they not considered pups?

 

[davenmandy]

Yes pups certainly nip at each other. They don't often take chunks out though, I guess that would depend on their age/size. Discus might take a nip out of a disc tho methinks.

 

[Ihsnshaik]

Not chunks but noticeable bites I have two brothers and the alpha hurts the smaller one but now they're fine together. It grows back within a few days just fine

 

[flukekiller]

Without pics I know it's hard but I guess chunks was the wrong wording...the pieces missing are probably less the 1/4 of the size of a dime