Gravel 3", with some big Vallisneria Giganthea sprouts, mangrove wood,
in which you can wedge some plants like Aponogeton.
Oscars dont like bright lights, maybe some floating plants.
Now I dont wanna be a wise ass, but 4 foot, 220 liters,
makes 122 centimeter, and 60 gallons.
Its the absolute minimum requirement for one Oscar.
Take two and they're not gonna be as social as they would like.
An Oscar can live happy with some other species like Geophagus.