03/31/2026
A store favorite
The metabolic rate of Pygmy Corydoras (Corydoras pygmaeus) seems to be more closely linked to water flow than just temperature. Most of us treat them like standard bottom dwellers, but they are actually mid water swimmers that do much better in river like, oxygen rich conditions.
In low flow setups, they often show a kind of subtle lethargy that many keepers assume is normal behavior. But when you increase the flow to around 6–8 times the tank volume and keep the pH between 6.4 and 6.8, something interesting happens. They become far more active and start displaying a real schooling behavior that is rarely seen in stagnant water.
It feels like we’ve been underestimating how active they can be simply because we’re not giving them enough movement and surface agitation.
