I keep one Oscar and he is enough for me.
I would get those heaters into the sump though.
Oscars bite them and will eventually break them.
Even with a heater guard I was nervous about this.
My oscar tank has plumbing too big to break, heaters in the sump, and some plastic plants for him to trash.
He will rip up all the plants, haul them "downstream" and build a fort to hide in.
I tried to keep him with a big catfish but the Oscar harassed the cat relentlessly, and this was a big spiny common pleco 10" long vs a 9" Oscar. Here he was in a petco 55 for about a year.
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Felix is 2 years old now, but I don't have good pics of him in his new tank yet. This is an old pic.
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