Colombia Tetra Issues

[nadajdui]

Hey all. My 5 Colombia tetras are constantly fighting it out, and I've noticed after the past week or so there are tears in some of their fins from their antics. They leave the danios I have in the tank alone. I'm just concerned over the tetras.
It's a 33 gallon tank (36"L 12"W 18"H). I would have thought it would have been enough room to house them comfortably. One of them seems to 'own' one half of the tank, and he chases and attacks the other 4.
Now, when it comes down to it I don't mind fish chasing each other around. But when their fins start getting torn, then I think I should do something about it. Only at feeding times do they relax enough to eat together without trying to kill each other.
Should I add more of them? I don't want to get rid of them.
Ph:6.5(give or take a little)
Ammonia:0
Nitrites:0
Nitrates:5-10
Hardness:1
The tank is planted with mostly Amazon sword plants, so they have places to hide. Maybe I should add more? Would that help?
Thanks.

 

[Tokis-Phoenix]

Usually the most successful solution to sorting out agression in fish which school together is to add more, which will either re-arange the pecking orders (which will change the bully from being the most dominant fish out of the group, to a less dominant position in the pecking order) or disperse the agression between the fish to levels much more tolerable.

I would advise adding another 2-3 tetras to the tank and then wait for 2 weeks for them to settle in and see if there are any differences in their behavior .

 

[nadajdui]

Okay, I think I will do that. Thanks

 

[nadajdui]

Just got 2 more today. I will add them to the main tank when they check out. Wish me luck hehe.

 

[vancouver]

Another thing that might work is to re arrange the tank.. It works with cichlids sometimes, might work with the tetras too..