Predators for a 40 gallon tank

  • We are currently upgrading MFK. thanks! -neo
Exodon's I believe would get to large. Being an active species, adults would need to be kept in an aquarium that is both long and wide. I think the minimum tank size would be a 55 gallon, but what are your dimensions?
 
Issue with exodons is you need 12+ and they chase each other a lot. Activity and enough space to evade attacks warrants at least 4 feet.
African butterfly fish, captive senegal bichir, or puffers get my vote. Look into Amazon puffers, all the fun of other puffers but they get along with other fish.
 
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