Telescope goldfish
Carassius auratus
intermediate careOverview
The telescope goldfish (Carassius auratus) is the fancy variety whose eyes protrude dramatically on stalks — the black moor is simply a black, velvet-scaled telescope. It comes in many colours (red, calico, panda and more), has a rounded twin-tailed body, reaches 15–20 cm, and lives 10–15 years. Its bulging eyes give poor eyesight and are easily injured, so a telescope goldfish is a slow, gentle fish that needs a hazard-free, carefully planned home.
Tank & water
Give one telescope goldfish 75 litres (20 gallons), plus about 40 litres per extra fish. Priorities:
- No heater, avoid chills: they are cold-water fish that prefer 18–23 °C as sensitive fancies.
- Smooth, safe décor: rounded ornaments and soft plants only — their protruding eyes damage easily.
- Gentle, strong filtration: over-filter with a good external filter but temper the flow.
Feeding
Telescope goldfish are omnivores whose weak eyesight makes feeding the main challenge. Use a quality sinking goldfish food they can locate on the bottom and allow plenty of time to eat. Add blanched peas and soft vegetables plus occasional frozen treats. Sinking food also curbs the surface air-gulping that triggers swim-bladder problems in round-bodied fancies. Feed modest amounts once or twice daily and stay on top of maintenance.
Tankmates
Keep telescope goldfish only with slow, gentle fancy goldfish — black moors, orandas, ranchu, lionheads, celestials and bubble-eyes. Avoid fast single-tailed goldfish (comets, shubunkins) and any nippy or tropical fish, all of which will out-compete or injure them. A group of similarly slow fancies in a spacious tank is ideal — plan numbers with how many fish in an aquarium.
The eyes only develop their full telescoping over the first months of life, so a young telescope may look almost normal before its eyes push outward. However pronounced they become, treat them as delicate for the fish’s whole life: a scratched or infected eye is one of the most common ailments in the variety, and nearly all cases trace back to sharp décor, dirty water or an unsuitable, boisterous tankmate.
Telescope goldfish — frequently asked questions
How big do telescope goldfish get?
Telescope goldfish reach around 15–20 cm as rounded, twin-tailed fancies. Like all goldfish they are heavy-waste fish needing a large, well-filtered tank — see how big do goldfish get.
Do telescope goldfish need a heater?
No. Telescope goldfish are cold-water fish that prefer the warmer end of the goldfish range, about 18–23 °C, as a delicate fancy. In a normal room they need no heater — see do goldfish need a heater.
Are telescope goldfish eyes fragile?
Yes. Their large protruding eyes are easily injured and their eyesight is poor, so they need smooth décor, gentle flow and slow tankmates. The black moor is simply a black, velvet-scaled telescope goldfish.
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