hey guys, how are you , xx well my 2 oscars are now 5 months old and are just about 4 inch, they are both red tiger oscars, but this past week one has gone really dark grey in colour, and the other very light green more olive, they act like they are sizeing each other up you know what i mean, in other words whos going to be boss, no fighting or lip locking, just going round each other very closely, and trying to push each other around, my question is why is there a differance in colour do you think it might be to do with domenance, but then which one is stronger,

No, I don't think the color of the fish has anything to do with a dominance issue, if there is one. If both fish came from the same batch then they won't necessarily be exactly the same color. You may find this behavior carries on for a while then stops. However, it may well be that one does become much more dominant over the other one. These things do happen and it may be that one the Oscar does get bullied, but cross that bridge if and when it happens

HI OFL.. i have to disagree ive been watching them very closely and i think the colour change has to do with dominance as nothing else has changed but one just going really dark and he seems to be in controll, while the other one is being passive but gone the olive colour, will keep watching the colour, they your the same untill a week ago, i will take vid for you xxx

was going to take vid, but they are back to the same colour..... confused.com... lol xxxxx

I have deffo seen Oscars change shade of black ...not so much change colour but just the top of the head mostly

I'm with you Kazzy. I have a red oscar and I use to have a tiger oscar. The tiger was the boss of the tank - no doubt. While my tiger was alive, the red never seemed to look red, kind of ashen/gray with red. Hard to describe. My tiger died... the red is now the only oscar in the tank and he has turned into a beautiful red color. He does turn black when he has his "battles" with the filter pipe and the heater.

Check out a recent thread I posted "Brooksie's babies". It shows how his color changes. I don't have any pics showing him all ashen.

kazzy wrote:

LOL. That's funny kazzy. "confused.com"
These O's change colors from time to time and I don't think the Oscars themselves even know why sometimes.

Sorry, I thought you meant changing color completely & staying like that. If you are talking about changing color every now and then then lots of animals do this, fear, aggression, camouflage, breeding. Fish use color for all sorts of reasons.

I have red Oscars, I used to have five, anyway one of the Oscars turned almost black, it was quite amazing, I had never seen this before. The fish was not dominant, in fact it was almost ostracized by all the other fish. Thinking it was ill I removed it and put it in a tank on its own and almost immediately it went back to a lovely red color again. I didn't put it back into the aquarium with the other Oscars, I found a new home for it.

i aggree with the boss.
Here's my tiger when i got him.



Here he is when just introduced to the new tank:


and this is him now,



quite a difference ,eh?
he still changes all the time.