Rainbow shiner

Notropis chrosomus

FreshwaterFish

Care at a glance

Temperature: 50–72°F (10–22°C)
pH: 6.0–7.5
Adult size: 3.1 in (8 cm)
Minimum tank: 20 gal (75 L)
Temperament: Peaceful
Social behavior: Schooling
Swim level: Middle
Difficulty: Medium
Breeding: Hard
Rarity: Rare
Origin: United States
Family: Cyprinidae

Overview

Rainbow shiners are peaceful, active shoaling fish that should be kept in a group of at least eight, as good numbers bring out their color and their lively, coordinated swimming. They occupy the middle water and do well in a coolwater community with other temperate, gentle species. They are undemanding feeders that take flake, small pellets, and frozen or live foods such as daphnia and bloodworm. Cool, clean, well oxygenated water is the key to keeping them healthy and colorful, so they are better suited to an unheated or lightly cooled tank than a tropical one. A tank around 75 liters or larger suits an active shoal.

In the wild

The rainbow shiner is native to the clear, cool streams of the Mobile River basin in the southeastern United States, across parts of Alabama, Georgia, and Tennessee, where it lives over gravel and stone in flowing water. It is a coolwater fish, comfortable at about 10–22 C and a pH of 6.0–7.5. Recreate its home with brisk current, a substrate of gravel and rounded pebbles, and clean, well oxygenated water. Some rock and driftwood and hardy planting round out the scene, but flow, oxygen, and cool temperatures come first.

Good to know

Notropis chrosomus is a North American member of the family Cyprinidae, one of the true minnows, reaching about 8 cm. For most of the year it is a modest silvery fish, but in the breeding season it transforms, males glowing with pink, blue, and violet iridescence and developing small white breeding tubercles on the head. It is an egg scattering spawner, often laying over the nests of other fish, and it is difficult to breed deliberately in the aquarium.

Did you know

In spring the male rainbow shiner earns its name, flushing with an unlikely mix of pink, blue, and purple that rivals many tropical fish, and sprouting rows of tiny white bumps called tubercles on its head. Outside that breeding window it is a plain silver minnow that gives little hint of the color to come.