My oscar is eating my other fish

[Rallysman]

Big fish eat little fish. Just the way it is.

When it comes to an oscar, if it will fit in its mouth, consider it gone. Even if the tank is large they will munch whatever they can.

 

[jm1212]

you need a bigger tank hands down. the oscar will eat anything that will fit in its mouth, which is pretty big as you can probably already tell.

some ID sharks get to 9' long and really do not have a place in hobbyists tanks IMO. even the "little" three foot species gets to be a hundred pounds or so.

the balas like to be in groups of at least 5. 180 gallons for 5 14" fish is a minimum.