Light's Bitterling (Rhodeus lighti)

Family: Cyprinidae

A peaceful omnivore cyprinidae from the Yangtze and Yellow River basins of China — moderate care.

Care parameters

Water temperature: 10–25 °C
pH: 6.5–7.5
GH hardness: 5–15 dGH
Adult length: 5–7.2 cm
Minimum tank: 72 L
Water layer: Mid-water swimmer; keep 6+
Difficulty: Moderate
Temperament: Peaceful
Origin: Yellow River basin, China

Species overview

Rhodeus lighti is a Cyprinidae from Yellow River basin, China. In the wild it prefers clear streams, rivers and still waters; in the aquarium it stays peaceful. Plan on 5–7.2 cm of adult fish at 10–25 °C. Related profiles: Rhodeus fangi, Rhodeus ocellatus, Rhodeus sinensis.

Native biotope

Habitat: Clear streams, rivers and still waters
Flow: Still to very gentle water
Dissolved O₂: Average oxygen needs

Aquascape & hardware

Substrate: Smooth gravel and sand with open floor space
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: Keep 6+; larger groups settle better
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: Egg-scatterer over fine plants; condition with rich foods and simulate seasonal changes

Frequently asked questions

How is Light's bitterling different from the rosy bitterling?

They are close relatives with the same mussel-dependent breeding. The main differences are distribution — Light's is centered on the Yangtze and Yellow Rivers — and subtle body proportions and color details.

Does it need cold water?

It is temperate rather than truly cold-water: the high teens to mid-twenties Celsius suits it. What it cannot tolerate long-term is warm, stagnant, oxygen-poor water.

Can I keep it with rosy bitterlings?

Yes, they coexist peacefully and make natural companions, though hybridization is a theoretical concern for dedicated breeders, so purists keep species apart.

Do they need soft water?

No — like most Chinese bitterlings they adapt across moderate hardness, as long as the water is clean, stable and cool to temperate.