Description

Butterfly koi are a variety of koi bred for their long, flowing fins and slender, elegant bodies.
They were originally developed by crossing koi with longfin Indonesian carp.

Key Features

• Long, trailing fins (most defining trait)

• More slender body than regular koi

• Size: 20–36 inches (50–90+ cm) when fully grown

• Lifespan: 20–40+ years with excellent care

• Colors: All traditional koi colors — kohaku, sanke, showa, platinum, yamabuki, ogon, etc.

• Temperament: Peaceful, social, hardy

They are not considered “show koi” by traditional Japanese standards, but are extremely popular in ponds worldwide.

🐡 Care Requirements

✔️ Pond Size

Butterfly koi grow large and need plenty of room.

• Minimum: 1,000 gallons for a small group

• Ideal: 2,000–5,000 gallons for adult koi

• Depth: 3–6 feet (protects from predators and temperature swings)

They cannot live long-term in indoor aquariums — they outgrow them.

💧 Water Parameters

Koi are hardy, but thrive best in clean, stable water.

• Temperature: 59–77°F (15–25°C)

• pH: 7.0–8.4

• Ammonia/Nitrite: 0 ppm

• Nitrates: <40 ppm

• Filtration: Very strong — koi produce heavy waste

• Aeration: High (waterfalls, air stones)

🍽️ Diet

Butterfly koi are omnivores.

Best Foods

• High-quality koi pellets (seasonal formulas)

• Leafy greens (lettuce, spinach)

• Fruits (orange slices, watermelon — treats only)

• Frozen foods (bloodworms, brine shrimp)

• Earthworms, insects

• Pond algae and natural grazing

Feeding Tips

• Feed 2–3x a day in warm weather

• Reduce feeding below 55°F

• Stop feeding at 50°F and below (digestive slowdown)

🧽 Pond Setup

Recommended Features:

• Strong filtration

• UV clarifier (keeps water clear)

• Plants (lilies, lotus, submerged oxygenators)

• Hiding spots (to reduce stress)

• Netting or deep zones (protection from predators)

Avoid:

• Sharp decorations (their long fins tear easily)

• Overcrowding

• Poor water circulation

🤝 Tank/Pond Mates

Butterfly koi are peaceful.

Good Mates:

• Other koi

• Goldfish (comets, shubunkins)

• Orfes

• Large, peaceful pond fish

Avoid:

• Predatory fish

• Small fish (may be eaten when koi get big)

🧠 Behavior

• Graceful, flowing swimmers

• Social and curious

• Easily trainable to hand-feed

• Can recognize their owners

• Tend to be calmer than regular koi because of slower swimming

🪺 Breeding

Butterfly koi breed the same way as standard koi:

• Spawn in spring

• Males chase females

• Eggs stick to plants or media

• Adults will eat eggs

• Requires a spawning mop or separate hatching area