Oscar tank mates

[LittlexSoul]

I have one large Oscar in a 125 gallon, 6ft. long tank. The Oscar is about a foot long. The tank is very open. I don't have substrate, just a couple of medium-sized decorations placed in the center, against the back of the tank. We've considered adding another fish, but I'm hesitant because this Oscar is my favorite fish I've ever had. I've had this guy for 7 years and I don't want to add anything that will cause problems. Should we try it or just leave him alone? What would you recommend?

 

[esoxlucius]

There's no way of knowing how such a big fish which is 7 years established in a tank is going to react to the sudden introduction of new fish.

If the big guy is happy, leave things as they are imo.

 

[tlindsey]

I have one large Oscar in a 125 gallon, 6ft. long tank. The Oscar is about a foot long. The tank is very open. I don't have substrate, just a couple of medium-sized decorations placed in the center, against the back of the tank. We've considered adding another fish, but I'm hesitant because this Oscar is my favorite fish I've ever had. I've had this guy for 7 years and I don't want to add anything that will cause problems. Should we try it or just leave him alone? What would you recommend?

Welcome aboard
I agree with @esoxlucius just leave it be.

 

[SilverArowanaBoi]

Perhaps you could try a catfish like an adult Striped Raphael catfish, but I agree with esoxlucius@ on this, leave things as they are.