Plecos!

I have a few carnivorous plecos. Although they eat meat, they are not predatory. With that said, they can be very aggressive and could hurt other fish during territorial disputes.
 
Plecos may fight over territory, and the weaker one may even get bullied to death. They can actually inflict some damage with various spines on the side of their heads.

As for eating other fish, I have been given several that were eating guppies. But the owner didn't believe that you have to feed plecos, so it was a survival thing for the pleco.

Any dead fish in the tank is fair game to any pleco.

ian
 
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