When breeding them be aware that some times males can kill the female in typical cichlid fashion. Breeding Oscars is easy as long as the water is clean and you raise the temperature from the normal 25°C (77°F) to 28°C (80°F). The female will choose a flat rock to lay her eggs (about 1000 eggs) and the male will fertilize them.
The opaque eggs will turn transparent in 24 hours and hatch after 2 or 3 days.
Watching a pair of Oscar fish breeding is an experience that is both thrilling and full of action. Over a period of several days the couple will work nonstop and build mountains of gravel around the aquarium. Like typical lovers they will chase each other, perform courtship dances and occasionally argue and fight. All these mood swings will be accompanied by intensifying color changes in the patterns on their skin.
Infertile eggs are white in color. As weird as it may seem, at times 2 females can engage in mating behavior.
Please remember that water quality is extremely important. A 25% daily water change and prompt removal of all food residues is mandatory, not only as a prior condition for spawning but especially after eggs and fry are present. When they are free-swimming offer the fry newly hatched brine shrimp several times per days.