[ERICVANCOUVER]

Hi,

I have 2 Golden tetras with red, discolor (blackish) caudal fin but not all the time
One day it's red then the next day it's gone or even red in the morning and normal on the evening
Do you know what is going on?
The 2 tetras are aggressive and sometime hiding behind plant then chasing other fish when they get closer
Ammonia 0, nitrite 0 and nitrate 5
Thank you

Eric

 

[Thelittlemermaid]

it could be finrot. is it the tips of their fins, or the entire fin?

 

[ERICVANCOUVER]

It's the beginning of the fin, the tips are fine

 

[Romad]

Could it be stress? Some of my fish darken up quite a bit when they're a bit stressed out - usually during water changes.