Shubunkin

Detailed Water Parameters

Temperature

Shubunkins are cool-water fish and are most comfortable between 65°F and 75°F (18°C – 24°C).

• Range: They are incredibly resilient and can tolerate temperatures from near-freezing (in deep ponds) up to 80°F for short periods.
• Heater: Generally, they do not need a heater if kept indoors. They prefer the natural seasonal temperature changes of a home.

pH Level and Hardness

They prefer slightly alkaline water with a pH range of 6.5 to 7.5.

• Hardness: They thrive in moderately hard water (10–12 dGH).
• The Nitrogen Cycle: Goldfish produce a massive amount of waste (ammonia) compared to Platies or Gouramis. Strong filtration is non-negotiable. You should aim for a filter that can turn over the entire tank volume at least 4 times per hour.

Feeding Routine and Quantity

When to Feed

Feed your Shubunkin once or twice a day. Because they lack a true stomach, they are designed to graze throughout the day.

How Much to Feed

• Quantity: Offer only what they can consume in 2 to 3 minutes.
• Dietary Needs: They are omnivores. Use a high-quality goldfish-specific pellet or flake as the base. Pellets are often better for larger fish as they are less messy.
• Fiber is Crucial: To prevent swim bladder issues (common in goldfish), provide plenty of plant matter like spirulina flakes, duckweed, or blanched peas (deshelled) and spinach.
• Treats: They love frozen Bloodworms, Brine Shrimp, and Daphnia, which provide essential proteins for growth.

Tank Mates and Social Compatibility

Friendly Companions

Shubunkins are fast, athletic swimmers. They should only be housed with fish that can keep up with them or stay out of their way.

• Other Single-Tails: They are best kept with Common Goldfish, Comet Goldfish, or Sarasa Comets.
• Pond Mates: In large setups, they live peacefully with Koi.
• Community Options: If kept in a very large tank (55+ gallons), they can live with Rosy Barbs, Zebra Danios, or Dojo Loaches, which also enjoy cooler water.

Fishes to Avoid

• Fancy Goldfish: Avoid slow-moving "fancies" like Orandas or Black Moors. The Shubunkins are much faster and will eat all the food before the fancies can get any, often stressing them out.
• Tropical Fish: Most tropical fish (Bettas, Gouramis) require water that is too warm for a Shubunkin’s long-term health.
• Tiny Fish: If it fits in their mouth, a mature Shubunkin will eventually eat it.

Physical Body Features

• Calico Coloration: The hallmark of the Shubunkin. They have a mix of blue, red, orange, and black splotches on a pearly (nacreous) background. The "Blue" base is the most highly prized.
• Streamlined Body: Unlike the round, egg-shaped fancy goldfish, Shubunkins have a long, slender body built for speed.
• Longer Fins: They often have longer, more flowing fins than the Common Goldfish, particularly the London and Bristol varieties.
• Size: They grow much larger than people expect—typically reaching 10 to 14 inches (25–35 cm).
• Longevity: These are long-term pets, often living 15 to 20 years (and sometimes over 30!) with proper care.

Tank Size Warning

Because they grow so large and produce so much waste, a single adult Shubunkin needs a minimum of 40–50 gallons. They are not suitable for small "starter kits" or bowls.