tetra missing part of tail

[rubyjess]

as stated my tetra is missing part of its tail
been monitoring the tank and it seems to be one of the other tetras causing the damage
as an emergency measure could i float a container on top of surface to seperate them
please help
as container i mean a food storage sort of thing till i go and buy some sort of proper container?

 

[rich311k]

What kind of tetra is it? What else is in the tank? How large is the tank?

 

[EndlersEatGuppies]

What kind of tetra is it? What else is in the tank? How large is the tank?

also

How many r in there?
What are the parameters?
Is it cycled?