Description

The Demekin is a Japanese variety of telescope goldfish known for its large, protruding eyes and flowing fins. It is closely related to the Black Moor and other telescope-eye breeds, but Demekin are often more brightly colored, especially red, orange, calico, or panda patterns.

Key Features

• Eyes: Large, protruding “telescope” eyes

• Shape: Rounded body, similar to fancy goldfish

• Size: 4–8 inches (10–20 cm)

• Colors: Red, orange, black, calico, panda, metallic, or bi-color variations

• Temperament: Peaceful, slow swimmer

• Lifespan: 10–15+ years with proper care

Because of their eye structure, they need gentle tankmates and obstacle-free environments.

🐡 Care Requirements

✔️ Tank Size

Fancy goldfish—including Demekin—need more space than most people expect.

• 1 Demekin: 20 gallons minimum

• Each additional: +10–15 gallons

• Filtration: Strong biological filtration, but gentle flow (their eyes make them poor swimmers)

Goldfish produce a LOT of waste—oversized filtration is a must.

💧 Water Conditions

Goldfish are cold-water fish.

• Temperature: 65–74°F (18–23°C)

• pH: 7.0–8.0

• Hardness: Moderate-hard

• Ammonia/Nitrite: Always 0 (they’re sensitive!)

• Flow: Low to moderate—strong currents stress them

🍽️ Diet

Demekin goldfish thrive on a varied omnivorous diet.

Best Foods:

• Sinking goldfish pellets (prevents gulping air)

• Gel foods (e.g., Repashy Soilent Green)

• Blanched veggies: peas (deshelled), spinach, zucchini

• Frozen or live foods: bloodworms, daphnia, brine shrimp

Feeding Tips:

• Feed 2–3 small meals per day

• Avoid floating pellets — risk of swim bladder issues

• Fast 1 day per week to improve digestion

🧽 Tank Setup

Safe Decorations:

• Smooth rocks

• Silk or soft plastic plants

• Sand or fine gravel

Avoid:

• Sharp decorations

• Hard plastic plants

• Tight gaps

• Strong filter intakes

Their protruding eyes get injured very easily.

🤝 Tankmates

Demekins are slow and visually impaired.

Good Tankmates:

• Other fancy goldfish (Ranchu, Oranda, Ryukin)

• Snails (mystery snails, nerites)

Avoid:

• Fast fish (danios, barbs)

• Nippy fish

• Comets or common goldfish (too fast, aggressive feeding)

🐾 Behavior

• Peaceful and social

• Slow swimmers

• May rest at the bottom when tired

• Can struggle to compete for food

Make sure they get enough to eat when kept with other fish.

🪺 Breeding

Breeding is similar to other fancy goldfish.

• Males chase females during spawning

• Eggs stick to plants/substrate

• Parents will eat the eggs—use spawning mops and remove adults

• Fry require special feeding (infusoria → baby brine shrimp)