Dwarf Pea Puffer (Carinotetraodon travancoricus)

Puffers don't have the usual separate teeth most fish do — their teeth are fused into four continuously growing plates, and without hard-shelled food like snails to wear them down naturally, those plates can overgrow enough to interfere with eating. That's part of why snails are a real dietary requirement here, not just an occasional treat, on top of being genuinely fun to watch this tiny puffer hunt down.

Care level: Moderate · Temperament: Semi-aggressive · Max size: ~1.5" · Min tank: 10 gal · Diet: Carnivore, snails + frozen foods