About 3 months ago I bought a lutino, and a black tiger oscar as babies and put them in their own 75 gallon with 10x filtration. They have both since grown to about 4.5 or 5 inches. At first I noticed the lutino would just out of nowhere ram himself into the black tiger for no reason at all. They could be just swimming along and the lutino would just smash into him.

Now it's to the point where the black tiger oscar isn't just taking it anymore. They square off with their mouths open and ram forward into each other. Is this behaviour going to stop or should I think about separating them? Can anyone please give me some advise? I love both these little guys and thought since I raised them together, and bought them as tiny babies that they would get along. I would appreciate any advise, thank you.

My water parameters are: Ammonia 0ppm
Nitrite 0ppm
Nitrate 20ppm
PH 8.0

I also do 25% waterchanges with vaccumming twice a week.

I'm afraid it would be the same as if you got two dogs that kept fighting, you would probably have to split them up if they keep doing it. Unfortunately, unless you have two tanks, you will probably have to rehome one of them.

Some people may suggest rearranging the tank but to be quite honest, I don't see this stopping the fighting if they just don't like each other, or maybe they are two males that both want to be top dog.

ha ha ha, that is the pain in the a#@ in fish keeping.
but they are too young to be dominance.... just keep
an eye and observed up to what extent bullying could be.
mouth trashing or lip locking is normal behavior when
growing, but trashing even in any part of the body means
its time to separate them permanently: rehoming or another
tank.

Wow, that is not gonna be kewl if I have to seperate them...I have just one payment left on a 120 gallon tank set-up. I already have 2- 75 gallons, (the other is an African Cichlid tank). This means I have to add another 75 gallon. Oh well, I can just look at it on the bright side...another tank! I don't want to give either Oscar up, I love them both. They'll just each have their own tank.

Thanx for the replies.

i also bought my two O's as babies, when they were growing they would quite often start lip locking and flaring up at each other.... they werent really aggressive with each other and neither ever really got hurt (scales/fins missing etc).

now that they are adults they dont display this behaviour as much any more and i have my happy boy and girl O in a 170 gal tank where they have layed twice and hatched their eggs once.

currently two years on from me buying them i am waiting for them to successfully raise their fry... and hopefully make me some money...

Well I went ahead and set up a 55 gallon tank for the tiger. I took one of the 110/500 Aquaclear filters that was on their tank, and about 20 gallons of the water, and 20 more gallons from my cichlid tank, and had a fully cycled tank set up in about 2 hours. I just put the new Aquaclear 110/500 on the original tank, (it has another one running on there also).

Do you guys think that 1 Aquaclear 110/500 is sufficient on a 55 gallon tank with just the one oscar in there?

Needless to say, (even though both oscars fought day in and day out), they are both VERY pissed off at me for making this move. I really hope they get over it!

in theory one ac 110 should be adequate for one oscar in a 55. just make sure to check your water parameters a couple of times a week to ensure that the nitrates stay low enough. you might need to do a couple of water changes a week with this setup but it should be fine.

I already do 25% waterchanges 2wice a week. I added an Aqua-Tech 60 power filter which does 360gph. I hope I'm not over-doing it, I think 860gph should be seriously sufficient.
Also I added a Jack Dempsey baby to the 75 gallon with my other Oscar in it. He follows the Dempsey around a bit, but no ramming or fighting, YET!

Does anyone know, if anything I could add in the 55 with the tiger that he would get along with, and not be cramped once he's bigger?

an angel fish would do.... less waste, slow growing,
and no risk with oscar

yes... angels do make great tank mates for Oscars... they can grow quite wide though, mine is around 4-5 inches long/wide

What kind of angel fish? I had some silver angels with a black stripes, (2 of them) in my 30 gallon, and they were so sensative, they just died, and I don't know what from. No other fish in that tank ever died either. Can someone post a link to a pic of the kind of angel that would live peacefully with my tiger O?