These guys have there very own personality from fish to fish. Just so happens that my largest male is as docile as John Coffey from The Green Mile. The smallest is the feistiest of the 3 males, as you can see in the vid . "John Coffey" keeps them in check so no big fights ever break out.
Sure can. Although you won't want to have smaller nano fish or shrimp in the tank, unless you don't mind them being Mac food every now and then. I started with a school of 10 cardinals when I first got these Macs. They were 1" juvies and as they matured to 3" young adults, my cards started mysteriously disappearing one by one. So did my Amano shrimps lol. Now I only have 2 cards left and zero Amanos.
I showed this to my wife and she said "ohh noo... you have enough fish" without me saying anything lol.
They remind me of two old men yelling at each other "you stole my pudding", "you broke my cain"
Yup these guys can get pretty mean looking but they've kind of developed this hierarchy amongst them. The big guy at the end is def the Alpha male while the smallest seems to be the feistiest of them all. Good thing he's the little guy otherwise there probably wouldn't be any order in the tank. The gentle old man still has a handle on things.... for now.