European minnow

Phoxinus phoxinus

Also known as Common minnow

FreshwaterFish

European minnow (Phoxinus phoxinus) — Adrien Pinot · CC BY-SA 3.0

Care at a glance

Temperature: 54–68°F (12–20°C)
pH: 6.5–7.5
Adult size: 5.1 in (13 cm)
Minimum tank: 45 gal (170 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: Hard
Rarity: Very rare
Origin: Europe and northern Asia
Family: Cyprinidae

Overview

The European minnow is a small, active, coldwater shoaling fish that must be kept in a group of at least eight, and preferably more, as it is highly social and nervous when kept in small numbers. It swims busily in the middle and upper water and is entirely peaceful, suiting an unheated tank alongside other temperate species of similar size and temperament. It is an eager feeder that takes flake, small pellets, and frozen or live foods such as bloodworm and daphnia. Cool, clean, well oxygenated water matters more to this fish than anything else. A tank around 170 liters or larger gives an active shoal room to move.

In the wild

The European minnow lives in cool, clear, well oxygenated streams, rivers, and stony lake shallows across Europe and northern Asia, from Britain and Spain eastward into Siberia. It is a coldwater fish that does best at about 12–20 C and a near neutral pH of 6.5–7.5, and it appreciates a seasonal drop in temperature. Recreate its home with brisk flow, a substrate of gravel and rounded stones, and a spotlessly clean, well oxygenated water column. Robust planting around the sides is fine, but the priorities are current, oxygen, and cool temperatures.

Good to know

Phoxinus phoxinus is a small, slim member of the family Cyprinidae that reaches around 13 cm, though most are smaller. It is one of the most widespread freshwater fishes in Europe and a familiar sight in clean upland streams. Spawning takes place in spring over gravel, where scattered eggs are left without parental care, and breeding this cool water species in the aquarium is difficult and rarely done. Breeding males develop dark, contrasting colors and small white tubercles on the head.

Did you know

The European minnow is a landmark in the study of animal behavior. In the 1930s the biologist Karl von Frisch showed that an injured minnow releases an alarm substance from its skin, later called Schreckstoff, that sends the whole shoal darting for cover. It was one of the first clear demonstrations of chemical alarm signaling in fish.