Beside the obvious size problems in a tank as small as a 125.
There is a water parameter disparity, Oscars and blue acara are both soft water, neutral to lower pH species.
The bocourti are hard water, high pH water species, preferted pH around 8.
I grew my bocourti out in a 150 gal, but had to move them to a 300 at a little oer a year, because they grew quite fast.
Although they are non-aggressive, if kept in too small quarters can get testy.



I kept mine with similar hard water high pH species Chuco intermedium
As the bocourti age, they become more and more vegetarian, and if fed a steady diet of some of the foods oscars prefer can have dietary issues.


Mine could go thru a head of romaine lettuce, and a dozen large dandilions or other succulent plants per day to keep intestines moving.