I just recently got a new 125 gallon tank, and i was thinking about taking my 2 adult oscars, which are both alone now, and putting them together in the 125. They were together from the time i got them, til about 4 months ago, because they outgrew the one tank they were in, and needed more space to themselves.


My tiger oscar is about 8 inches from head to tip of tail, and my long-finned oscar is right about 8.5 inches from head to tip of tail. The long finned oscar is currently sharing a 65 gallon with 2 small african cichlids, and has a real mild temperment. The tiger oscar is in a 55 gallon alone, and is a bit more aggressive, but not horribly bad.

Would it be a bad idea to put them together in my new 125 gallon? It will be just those 2, and a few different, larger, cichlids. There are plenty hiding spots in the 125, and has excellent filtration to it. But the thing im worried about, is the long-finned oscar having its fins destroyed by the tiger oscar.

Any advice on this would be greatly appreciated! Sorry for the long question.. These are the first oscars ive ever had, and have fell in love with them from first time i brought them home

This is something only trying will answer... I have had it work before, and I have seen situations where it has gone horribly wrong!

IF you try it, make sure you are there to observe for several hours. And make sure you can move one back if it goes bad!

Good Luck!

I was worried id get that answer lol. I think i will give it a shot, and see how it goes. If it does go sour, i can always just put one of them back in their original tank. Thank you for the reply! Its much appreciated!

what concern me is the long fin one...very susceptible to fin damage
if bullied by the tiger.... i suggest you get some sort of divider like
this one so that you can observed if they will attacking each other even
with this barrier... if not, you can remove the divider but can easily put
it back just in case....

This is how I have successfully dealt with situations like yours, first make sure there is no dominant ground established from either Oscar if your introducing one to the others tank male sure you move all decorations and rocks to take out any territory that had Been formed, make sure you add the calmer Oscar with the cilchilds that live with it in together because they will all stand up for each other, in regards to the fins, don't be stressed all fins grow back, good luck

Thank you guys for the info! It will be a new tank for both the oscars, so luckily i wont have to worry about one of them already claiming a territory. Im hoping that with all space in the tank, theyll kind of keep to themselves. Theyre both beautiful oscars, and i would love to have the both of them together. I have kept the long-finned from eating live food, hoping to keep down the aggression. The tiger does get live food, but only once every cpl months, and is not very aggressive with them. So hopefully theyll get along ok. Thanks again for the help guys! Its much appreciated! Ive tried to get info on a few other forums, but this is the only site ive gotten any advice on.

Yeah you will just have to try it and see what happens. There may be some signs of aggression an you may have to decide when its time to seperate them. There can be a fine line. But typically some miner lip locking or gill flaring is okay. You just don't want to see anything to violent that would severely damage one of your O's.

I believe Noddy introduced a larger tiger Oscar to his tank with a large Red Oscar. He may have a couple of extra tips.



@Paul... what did you use for the divider and how did you secure it in the tank?

cebosound wrote:

i just put 1 sucker cup on every corner of the grate...
and it looks like letter C when you look at the top view
just cut the grate a little bit wider than the total width
of the tank....

cebosound wrote:


true dat, i put a 7,5" tiger in my 11" gentle Red's tank.
mind you the tank is a little bigger than yours.
a vid says more than a thousand words...or something like that.
This is the moment i put Hope, the tiger into the tank
my red is showing the tiger it's his territory, pretty rough from time to time, but no damage at all.:



Few days later Hope started to feel at home, and they were testing strenght and comparing mouth size.
This looked promising allready:



and nowadays they formed a pair and they never leave eachothers side.
Only toying and more than friendly behaviour :



quite a lot of vids, but imo this shows what it looks like when the oscars are gonna get along.
Keep a close watch though, for i do know i've been lucky!