Carinotetraodon travancoricus (Also called the Pygmy Puffer, Dwarf Puffer, or Malabar Puffer among many names) is one of, if not the, smallest species of pufferfish. These diminutive fish barely reach 1" long! Highly intelligent for their size, pea puffers need a well-structured tank to keep them well-stimulated. Dense tangles of driftwood and plants are ideal. Most aquarists keep pea puffers in a single-species tank; like most puffers, pea puffers can be quite aggressive. If you are to attempt to keep them with other fish, care must be taken that any tankmates are swift and robust enough to escape the puffers; inversely, they mustn't be so large or aggressive as to attack or outcompete the puffers. A single puffer can be kept in a tank as small as 5 gallons, and a group can be kept in 10-20 gallons of space.