A Firemouth could definitely hold its own. If its the looks you don't like that is a different story but don't let the temperament fool you. I had one that was to aggressive for the tank so I put it with my larger peacocks and it dominated that tank.
Agreed, firemouths are more durable than they appear. I have a male that lives with a Managuense that could inhale him but he will actually flare at the jag on occasion. Granted I'm not sure the jag even notices the flaring lol.
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