Food Aggression

[A3Sneezer]

You could try feeding them separately if peach starts to look skinny.

[Krispy]

We have 12 in a planted viv. Almost 3 years strong... They will fight from time to time... perhaps you need to up your feeding pattern... bombers dont really like being touched, and its not really recommended either.
Yes, they are right about social structure, or pecking order. So after a little while mario should calm down.

Also, males have a courser texture to their skin than females.