I never kept an adult oscar with polys but i dont know that i would trust a big O with some of the more common upper jaw polypterus like delhezi, moke, polli, palmas, gold dust, and especially sens.
Your probably going to be better off with one of the larger lower jaws endlicheri, congicus, and lapradei. Also weeksii (slow growing), teugelsi, and ornates would get large enough.
Your probably going to be better off with one of the larger lower jaws endlicheri, congicus, and lapradei. Also weeksii (slow growing), teugelsi, and ornates would get large enough.