Thayeria boehlkei
Holds an unusual head-up tilt at rest, with a black band running from gill plate to the lower lobe of the tail. The angle is distinctive in a planted tank and reads well against green backgrounds. Tougher than most tetras.
Penguin Tetra (Thayeria boehlkei) reaches 5–6 cm as an adult and needs a minimum tank of 90 L. Native to Amazon basin, it lives in the mid to top water column with a peaceful temperament. Aim for 22–28 °C, pH 5.8–7.5, and 2–15 dGH hardness. Lifespan is 4–6 years with good care. Keep penguin tetra in groups of 8+, yes schoolers need numbers to display natural behaviour. Diet: omnivore, Flake, micro pellets, frozen and live small foods. Plant-safe: Yes. Shrimp-safe: Yes (with adults).
Care at a glance
Holds an unusual head-up tilt at rest, with a black band running from gill plate to the lower lobe of the tail. The angle is distinctive in a planted tank and reads well against green backgrounds. Tougher than most tetras.
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Part of our complete guide to aquarium fish for the planted tank.
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The parameters that decide whether penguin tetra fits in your tank.
Mid to top
Yes
Group of 8+
Characidae
Omnivore
Flake, micro pellets, frozen and live small foods.
4–6 yrs
Medium
Amazon basin
Amazon basin
Tank-mate safety and the species this one is documented to thrive (or fail) alongside.
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Penguin Tetra (Thayeria boehlkei) needs a minimum tank of 90 L. They live in the mid to top water column and should be kept in groups of 8+, so a longer footprint matters more than depth.
Target 22–28 °C, pH 5.8–7.5, and 2–15 dGH hardness. Acclimate slowly when moving them between water sources.
Shrimp safety: Yes (with adults). Plant safety: Yes.
Penguin Tetra are omnivore. Flake, micro pellets, frozen and live small foods.
On Fin & Stem's 1–5 difficulty scale this species rates 1/5. Almost unkillable, a solid first-tank choice. Breeding difficulty: medium.
Typical lifespan in a well-maintained tank is 4–6 years.
A planted tank is a system. Pair this fish with one entry from each other pillar to plan the whole scape.
