Oscar and Green Terror aggression issues

[no69scope420]

I've got a 90 gallon tank and I've had an Oscar for about 2 years. I used to have a pair of jewel cichlids in there as well but when I moved a few months ago I gave them away.

Since the move, the tank was a bit empty with just the Oscar and a BN pleco, so after doing some research on potential tankmates I picked up a green terror a handful of days ago. I figured if the Oscar could handle 2 jewels it could handle one similarly sized fish.

So far it's going pretty poorly. Despite the Oscar being about 9 inches and the GT being about 4 inches, the GT bullies the **** out of the Oscar, and now he's spending almost all of his time in a corner. Neither have done any damage to each other, but I've heard the Oscar bump against the lid of the tank! I added some more rocks this evening to give the GT some cave cover but after a few hours the Oscar is backed into the corner again.

I posted about this in the aquarium subreddit and a lot of people suggested getting more cichlids to act as dithers. It seems counterintuitive to get more aggressive fish, especially when I think my tank is at about full capacity.

In all likelihood I'm going to return the GT to the store and pick up some silver dollars for a more peaceful tank, but I was curious if anyone has some other advice. I know SDs are popular dithers, would I have enough room in my tank for SDs, a GT and an Oscar? Is it really possible to curb aggression by adding more fish?

 

[Azedenkae]

There are only two options here. Remove the GT or get more cichlids.

The people on Reddit is right in this case. Cichlid aggression works largely the same (there are exceptions), basically they are aggressive, so they either have to be by themselves, or there is so many that yes, aggression is still there, but it is spread out. And they tend to fight amongst each other.

Getting SDs is zero guarantee that the GT will calm down. It is likely to still go after the oscar, so that can be rather pointless.

 

[no69scope420]

There are only two options here. Remove the GT or get more cichlids.

The people on Reddit is right in this case. Cichlid aggression works largely the same (there are exceptions), basically they are aggressive, so they either have to be by themselves, or there is so many that yes, aggression is still there, but it is spread out. And they tend to fight amongst each other.

Getting SDs is zero guarantee that the GT will calm down. It is likely to still go after the oscar, so that can be rather pointless.

When I was little we kept a 60g cichlid tank, I guess I'm surprised to learn big cichlids play by the same rules. Could you suggest any breeds small enough to buy overstock my tank?

 

[Azedenkae]

When I was little we kept a 60g cichlid tank, I guess I'm surprised to learn big cichlids play by the same rules. Could you suggest any breeds small enough to buy overstock my tank?

A bunch that gets to about 20cm or so should be fine. I'd say probably get seven or so? That should be a good number.