Gang Member Tetras

[Allan]

I've got 6 "candy" tetras (look exactly like bleeding hearts but colored--didn't know they colored them until after the purchase) & 2 black skirt tetras in a 15 gallon. I read that they school when spooked, but not so much in displaying normal behavior.
However, mine have actually set up 8 different territories in the tank, & they all chase & nip each other if their space is violated. It's like having gangs in my tank as opposed to a community environment! One black skirt has gotten so much harassment & fin nipping that I believe he'll die soon. Has anyone had similar experiences with these "community fish?" My water's a bit alkaline & hard for tetras, but mine are thriving in terms of personal health--very colorful & nice open fins. Could that be causing any of this? Will adding more plants (plastic for now) reduce this territorial bahavior? None of the tetras bothered my Gold Mollys when they were in the tank--could this be some mating thing? Please help!

[fishman0]

My tetras stake out territoies on the bottum of the tank and have small fights if one gets in the other ones space. And they only school if if I put my hand in quickly or if I turn off the lights then they school for about 20 seconds and then go back to the bottum.

[Slacker]

My zebras, amazingly enough, seem to have done something similar. There are two smaller ones that band together against the others but they each have different areas marked "thiers" and if another comes in...its on.