Amazon Puffer ~ Colomesus asellus

The Amazon Puffer, also known as the South American Puffer, is a small, active freshwater pufferfish known for its engaging personality and constant swimming. Native to the fast-flowing rivers of the Amazon Basin, this species stands out as one of the few true freshwater puffers that thrive in groups. Its charming expressions and unique behaviors make it a favorite among experienced aquarists.

Size: 2.5-3 inches
Lifespan: 8-10 years
Temperament: Peaceful to mildly nippy, inquisitive
Group/Solitary: Best kept in groups of 3 or more
Food: Carnivorous; snails, crustaceans, live/frozen foods (bloodworms, brine shrimp), occasional soft pellets
Water Requirements: 74-80°F, pH 6.5-7.5, soft to moderately hard water

Care Instructions

Amazon Puffers thrive in well-oxygenated aquariums with moderate to strong flow, mimicking their native river habitats. A tank of at least 30 gallons is recommended for a group of three, with additional space for more. Provide smooth rocks, driftwood, and plants to create a stimulating environment without sharp edges, as puffers can be prone to injury.

This species is social for a pufferfish and tends to do best in small groups, which reduces aggression and promotes natural behavior. However, monitor for nipping, especially when feeding or establishing territory.

Amazon Puffers are strict carnivores with fast-growing teeth that must be managed through diet. Feed crunchy foods like ramshorn or pond snails, shrimp, and shelled mussels to help wear down their teeth naturally. Supplement with frozen bloodworms and brine shrimp, and offer soft sinking pellets as part of a varied diet.

Due to their sensitivity, stable water quality and frequent partial water changes are key. They are not beginner-friendly but can thrive under the care of an aquarist familiar with their needs.

Fun Fact: Amazon Puffers are one of the few freshwater puffers that can safely be kept in groups. Their constant swimming and expressive eyes make them one of the most interactive fish in the hobby!