Goldfish Breeding Guide — From Spawning to Raising Fry

Goldfish breeding has been enjoyed in Japan as a traditional hobby for centuries. With knowledge of spawning timing and proper environmental setup, breeding can be enjoyed at home.

Breeding Season

The optimal goldfish breeding season is spring (March-May). Spawning behavior begins when water temperature exceeds 18C.

• Winter cold management: Exposing fish to 10-15C in winter makes spring spawning more likely
• Temperature target: 18-22C is ideal for spawning
• Daylight hours: 12-14 hours of light promotes spawning

Breeding Difficulty by Variety

• Wakin/Comet: Very Easy -- most straightforward
• Ryukin: Relatively Easy
• Black Moor: Relatively Easy
• Oranda: Moderate
• Ranchu: Difficult
• Tosa-kin: Very Difficult

Spawning Preparation

1. Parent selection -- Choose healthy, well-built specimens over 1 year old
2. Sexing -- Males develop white breeding tubercles on pectoral fins and gill covers during breeding season
3. Spawning substrate -- Set up spawning mops, netting, or artificial grass
4. Conditioning -- Feed high-protein foods (bloodworms, brine shrimp) to build stamina

Spawning and Fertilization

• Spawning behavior: Males chase females, pressing against them
• Spawning: Usually occurs in early morning; female deposits eggs on substrate
• Egg count: 500 to several thousand depending on variety and size
• Fertilization: Male releases milt immediately after egg deposition

Egg Management and Hatching

1. Isolate eggs -- Move spawning substrate to a separate container (parents will eat eggs)
2. Methylene blue -- Add lightly to prevent fungus
3. Temperature management -- Approximately 5 days at 20C, 3 days at 25C to hatch
4. Remove unfertilized eggs -- Use pipette to remove eggs that turn white and cloudy

Fry Rearing

• Just hatched: 2-3 days of growth using yolk sac nutrients; no feeding needed
• Initial feeding: Newly hatched brine shrimp or powdered fry food
• After 2 weeks: Daphnia, finely crushed prepared food
• After 1 month: Regular goldfish food (fine granule type)

Selection Points

"Selection" is crucial in fancy goldfish breeding.

• 1st selection (2 weeks): Remove obvious deformities and color abnormalities
• 2nd selection (1 month): Select based on body shape and tail form
• 3rd selection (2-3 months): Verify breed-specific characteristics are present
• Culled fish: Many are still beautiful as common goldfish

Benefits of Buying on Buri-Choku

On Buri-Choku, you can purchase directly from goldfish breeders with competition awards. Verify bloodlines and selection criteria directly, finding ideal starter specimens for breeding programs.