Corydoras Pygmaeus

Scientific name: Corydoras pygmaeus

Adult size: up to 3 cm

Origin: Rio Madeira basin, Brazil

Water: 22–26 °C, pH 6.4–7.4, 0–8 dGH

Group: 6 minimum, 10 or more better

Diet: small sinking dried foods, tiny frozen and live foods

Temperament: very peaceful, shoaling; ignores adult dwarf shrimp, may eat shrimp fry

The pygmy cory is a miniature armoured catfish that stays under 3 cm, native to the Rio Madeira basin in Brazil. Unlike most of its relatives, which live on the bottom, it spends much of the day hovering in midwater, fanning its fins in place before darting off in a group. It is a shoaling fish, meaning it needs company of its own kind to feel secure, and a group of six is the minimum; ten or more brings out far more confident behaviour. Because it is so small and easily pushed away from food, it does best with other tiny, calm fish rather than in a busy community. Aquarium Co-op notes that pygmy cories leave snails and adult dwarf shrimp alone but may accidentally slurp up a baby shrimp while foraging. Like all cories it feels for food with barbels, the whisker-like sensory organs around the mouth, which wear down on sharp gravel or dirty substrate.

Water: 22–26 °C and pH 6.4–7.4, hardness 0–8 dGH, so soft and around neutral. Keep the substrate clean with regular gravel vacuuming and partial water changes.

Tank and planting: smooth sand or fine rounded gravel to protect the barbels, with plants, driftwood and roots for shelter. A gentle filter flow and dim light help this shy fish come out.

Feeding: small sinking foods: micro pellets, crushed wafers, frozen daphnia, cyclops and baby brine shrimp. Make sure food reaches the bottom before faster fish clear it.