Black Moor Goldfish

The Black Moor goldfish is one of the most striking fancy goldfish varieties — a slow-swimming, velvet-black fish with dramatic protruding telescope eyes that give it an endearingly wide-eyed expression. Despite their delicate appearance, Black Moors are among the more robust fancy goldfish varieties when kept in properly sized, cold, well-filtered tanks. They are not tropical fish and must not be kept with most community aquarium species.

Taxonomy & Classification

The Black Moor is not a separate species but a selectively bred variety of the common goldfish, Carassius auratus — the same species as every other goldfish variety from comets to orandas. It is distinguished by two features: a velvety, jet-black coloration (caused by melanophore cells) and protruding, telescope-style eyes (a genetic mutation affecting eye socket development). The variety originated in China and has been maintained through centuries of selective breeding.

Natural Habitat

As a fully domesticated captive variety, Black Moors have no wild habitat. Their ancestor, the wild carp Carassius auratus, is native to slow-moving, often murky freshwater across East Asia — rivers, lakes, and ponds. Black Moors retain the cold-water preference of their ancestor and are NOT tropical fish.

• Cold to temperate water: prefer 65–72°F (18–22°C); do not require a heater in most indoor environments
• Slow-moving water: fancy goldfish varieties are poor swimmers compared to single-tailed goldfish; strong currents stress them
• High oxygen requirement: goldfish have high metabolisms and need well-oxygenated water
• No tropical environment: temperatures above 75°F stress fancy goldfish long-term

Water Requirements

Tank Setup

A 20-gallon tank is the minimum for a single Black Moor, with 10 additional gallons per additional fish. Fancy goldfish produce heavy waste and require substantial filtration:

• Oversized filtration: a filter rated for at least twice the tank volume; goldfish produce 2–3× the waste of most tropical fish
• Smooth decor: avoid sharp decorations — the telescope eyes of Black Moors are fragile and easily scratched; any wound on the eye becomes infected quickly
• Wide open swimming space: fancy goldfish are clumsy swimmers; they need unobstructed space to maneuver
• No heater needed: Black Moors prefer cooler water than room temperature in most climates
• High oxygen: air stone or surface agitation; goldfish need highly oxygenated water

Telescope Eye Care

The Black Moor's most distinctive feature — the protruding telescope eyes — is also its most vulnerable. The eyes protrude far from the socket, making them susceptible to:

• Physical injury: catching on sharp decorations, rocks, or filter intakes
• Infection: any wound on the eye quickly develops into Pop-Eye (exophthalmia) or bacterial infection
• Cloudy eyes: bacterial or water-quality related opacity of the cornea

Black Moors also have significantly reduced vision compared to normal-eyed goldfish, which affects their ability to compete for food at feeding time.

Diet & Feeding

Black Moors are omnivores and enthusiastic eaters. As with all goldfish, overfeeding is a common problem:

• Sinking pellets preferred: goldfish that gulp air at the surface while eating floating food often develop swim bladder problems; sinking pellets reduce this risk
• High-quality goldfish formula: wheat germ-based pellets in cool water (under 65°F); higher-protein formulas at warmer temperatures
• Vegetables: blanched peas (shelled), zucchini, spinach — excellent fiber source and helps prevent constipation
• Frozen food: blood worms, brine shrimp — in moderation as treats

Compatible Tank Mates

Black Moors should only be kept with other fancy goldfish varieties of similar swimming ability:

• Other fancy goldfish (ryukin, oranda, ranchu, telescope eye varieties)
• Bubble-eye and celestial goldfish (similarly impaired swimmers)
• Dojo loach / weather loach (tolerates cold water; peaceful scavenger)

Avoid: Single-tailed goldfish (comet, shubunkin, common) — they outcompete Black Moors for food and may nip fins. Tropical fish — temperature incompatibility. Any fast or nippy species.

Common Health Issues

• Swim bladder disease — floating or sinking abnormally; caused by overfeeding, constipation, or bacterial infection; fast for 2–3 days and feed blanched peas
• Pop-Eye (Exophthalmia) — eye(s) swelling outward further than normal; bacterial infection; treat with antibacterial medication
• Eye injury / cloudy eye — physical trauma or bacterial infection; remove sharp objects; treat with antibacterial medication and salt bath
• Ich — white spots; treat with temperature increase and medication; goldfish tolerate most ich treatments
• Fin rot — usually secondary to water quality; increase water change frequency and treat with antibacterial medication

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