Oscar being a bully

[G8zzaj]

Hey everyone,

Had a 4-5inch oscar in a 90 Gal for about a month on his own had a full on sulk down by the filter for first 3-4 days but was then fine.

Added a tank mate yesterday of the same size and the first Oscar has been a complete knobhead! chasing, biting and bullying the new one. New guy has about 7 or 8 bite marks on him now and is just cowering under the drift wood in the middle of the tank.

Any suggestions what to do? will this aggression subside usually? I don't have any other tanks other than my 180 Gal that I'm cycling so don't really want to move either of them to that?

Will adding 4 or 5 Silver Dollars help?

 

[duanes]

Once you give a territorial cichlid (like an oscar) a tank to itself for a month, it owns that entire tank, and it is unlikely it will see any other cichlid added as anything except something to be eliminated.
adding cichlids one at a time to a tank is usually not a good idea.
If you're planning on a cichlid community in your 180, its best to add them all together as juvies at once, and allow them to set up a hierarchy on their own.
That's not to say there won't be casualties, a 180 is not a large tank, when it comes to large cichlids
I believe a 180 is only large enough for 2 or 3 oscars that have grown up together from juvie size.
and a 4-5" oscar is young, so will soon outgrow a 90gal alone quickly,

 

[neutrino]

Once you give a territorial cichlid (like an oscar) a tank to itself for a month, it owns that entire tank, and it is unlikely it will see any other cichlid added as anything except something to be eliminated.

Agree...

 

[G8zzaj]

Thanks both.

remobed the first Oscar and added another and both getting on well and waiting for big tank to cycle and move ober