River Gudgeon (Sarcocheilichthys variegatus)

Family: Cyprinidae

A peaceful omnivore cyprinidae from Japan, the River Gudgeon patrols mid-water alone or in pairs — moderate care.

Care parameters

Water temperature: 18–26 °C
pH: 6.5–7.5
GH hardness: 5–15 dGH
Adult length: 10.4–14.9 cm
Minimum tank: 149 L
Water layer: Mid-water swimmer
Difficulty: Moderate
Temperament: Peaceful
Origin: Japan

Species overview

A Cyprinidae species native to Japan: Sarcocheilichthys variegatus lives mid-water swimmer over clear streams, rivers and still waters. Peaceful. Adults reach 10.4–14.9 cm. It is one of the aquarium-kept Sarcocheilichthys species we profile, alongside Sarcocheilichthys nigripinnis, Sarcocheilichthys sinensis, Sarcocheilichthys davidi.

Native biotope

Habitat: Clear streams, rivers and still waters
Flow: Moderate flow
Dissolved O₂: Average oxygen needs

Aquascape & hardware

Substrate: Fine sand
Hardscape: Driftwood, water-worn stones and shelters that mimic the native biotope
Plants: Hardy plants on hardscape; keep the floor open

Temperament, diet & tankmates

Schooling: Solitary, pairs or small groups
Diet: Omnivore; quality prepared foods with variety
Recommended tankmates: Amur False Gudgeon — Similar size and water needs
China-Bitterling — Similar size and water needs
Acanthorhodeus chankaensis — Similar size and water needs
Avoid keeping with: Large aggressive cichlids — Bullying and injury risk
Known fin nippers — Constant stress and fin damage

Breeding & notes

Sexual dimorphism: Males are typically slimmer and more intensely colored; females fuller-bodied
Breeding method: Spawning; condition with rich foods and simulate seasonal changes

Frequently asked questions

Is River Gudgeon easy to keep?

Difficulty: moderate. Peaceful. Solitary, pairs or small groups.

What temperature and water chemistry does River Gudgeon need?

Aim for 18–26 °C. Standard heater to hold the mid-range steadily; community-standard range; verify locally.

How big does River Gudgeon get, and what tank size?

Expect 10.4–14.9 cm as an adult, living mid-water swimmer. A 149 L tank or larger gives it room.

What does River Gudgeon eat?

Omnivore; quality prepared foods with variety. Vary the menu — quality flakes or pellets plus frozen or live foods.

Can River Gudgeon live with other fish?

Peaceful. Recommended tankmates: Amur False Gudgeon — Similar size and water needs, China-Bitterling — Similar size and water needs, Acanthorhodeus chankaensis — Similar size and water needs. Avoid Large aggressive cichlids — Bullying and injury risk, Known fin nippers — Constant stress and fin damage.

Where does River Gudgeon come from?

Its home waters are Japan — clear streams, rivers and still waters, with moderate flow.

How does River Gudgeon breed?

In the aquarium: spawning; condition with rich foods and simulate seasonal changes. Males are typically slimmer and more intensely colored; females fuller-bodied.