Freshwater Barracuda ???

Silver Dollars
Severums
Chocolate cichlids
etc...

This also includes pretty much anything else that is not too aggressive, or too small. Also, make sure you have a plenty of space to house these fish. You need at least 55 gallons for the freshwater barracuda, plus space for it's comanions.
 
You also need brackish water for the FW barracuda. The name is a little deceiving but they come from brackish rivers and have even been found at sea. They're generally a species only fish, they're nippy and have BIG teeth. They can do pretty bad damage to most fish. They're pretty much like mollies with big teeth. Feed them gut loaded feeder guppies as most will only take a moving meal. You could try silver sides, but I think they will only readily accept live food.
 
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