I am looking to get either a fish or crab that will eat other fish. Not that it would be the only thing that it eats, but to be a treat for the fish/crab (and also for me to watch). I'm leaning more towards crabs but I don't know which ones are that aggressive.

most freshwater crabs are not fully aquatic. So unless you want to build some stuff in your tank for it to climb out on, you may want to stick to fish. I think cichlids feed on other fish but since i havent had any, i cant say for sure.

I would definitely be willing to set up a half aquatic tank. I also only plan on having a smaller tank so I don't think I'll have the space for cichlids.

I've wanted to dive into one myself.. but i dont have the room. lol would be a cool set up to have though

It takes all sorts...mostly carbs that are found to eat fish,find them allready dead.then they pick them apart with there nipper..

oscars are good theres videos on youtube of them eating everything, worms, fish, snakes, lizards, mice... i have a tiger oscar in my 30 gallon until i get a 55

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Current Tanks:
90G,30G,10G,10G,5G,38G,20G

Please don't get a fish just because you want to watch it eat other fish. Aside from the fact that a diet comprised primarily of fish is a good way to cause undue health issues and death for your pet, you should be getting an animal because you enjoy the way it looks, acts, and interacts with you and other fish rather than to just watch it ravage another living animal.

Please think your decision over carefully.

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