tiger oscar biting clown knife

Question
Help my tiger Oscar who is about 9" long won't stop biting my clown knife who is 11" long. I have an angel fish, Jack dempsey and 2 sucker fish in the tank as well and he doesn't bother any of them. what do I do to stop him from doing this?

Answer
Hi Terri,
I'm really sorry but I don't think there's much you can about your Oscar's aggressive behavior. As far as cichlids go, if they decide they don't want to share their space with another of fish then there usually is not stopping them. Oscars tend to be very territorial, they can also be fine with other fish when they are young or a juvenile, but as they get older they may decide that they just don't want to share their space anymore. This is of course especially true if the tank is too small or there's just too many fish in the tank.
The Oscar may eventually move on to the other fish as well if you don't watch out.

You could try relocating the Clown knife fish in another tank or relocate the Oscar himself. I know this is a pain but its just something we all deal with when you get into big and territorial fish like Oscars.

I really hope this helps!
Best wishes,
Karen~