Zebra Danio (Danio rerio) | Live Freshwater Community Fish

The Zebra Danio (Danio rerio) is one of the most iconic and beginner-friendly freshwater fish in the hobby — instantly recognizable by its horizontal blue-black and silver stripes and famously active swimming behavior. They're hardy, peaceful, and constantly on the move, making a lively school the perfect "starter shoal" for a new community tank or a great splash of motion in an established planted aquarium. Care level is beginner; temperament is peaceful (active but not aggressive).

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• Tank Size: 10 gallons minimum — 20+ gallons strongly preferred for a proper school of 6 or more
• Temperature: 64–77°F (18–25°C) — tolerant of cooler temps; can be kept unheated in many homes
• pH: 6.5–7.5
• GH: 5–12 dGH
• Diet: Omnivore — quality flake or micro-pellet daily, supplement with frozen daphnia, brine shrimp, or bloodworms a few times a week
• Schooling: Yes — keep in groups of 6 or more for proper behavior; lone Danios can become stressed and nippy
• Temperament: Peaceful but very active — avoid keeping with slow-moving or long-finned tankmates that they may chase or fin-nip
• Max Size: ~2.5 inches (6 cm)

Zebra Danios are peaceful schooling fish that thrive in active community tanks. Their constant movement can stress shy or slow-moving tankmates, so match them with similarly active fish or species comfortable holding their own.

Good tank mates: Other danios, white cloud minnows, larger tetras (black skirt, serpae, lemon), peaceful barbs, corydoras catfish, otocinclus, peaceful rasboras, dwarf gouramis (in larger tanks), nerite snails, and Malaysian trumpet snails.

Avoid: Bettas, angelfish, slow long-finned fish (fancy guppies, fancy goldfish), and very small or shy species that may be stressed by constant darting movement. Avoid aggressive cichlids and predatory fish that view small danios as food.

• Quality flake & micro-pellet foods — daily staple diet
• Water conditioners & care — for water changes and tap-water dechlorination
• Water testing kits — monitor ammonia and nitrate during cycling and beyond
• Filter media — replace mechanical media monthly, biological media rarely
• Freshwater plants — danios love darting through plants like jungle val and hornwort

How many Zebra Danios should I keep together?
At least 6 — they're a true schooling species and feel safest in numbers. Larger groups (10+) show off the most natural behavior and reduce stress-related fin nipping.

Do they need a heater?
Not always. Zebra Danios are unusually cold-tolerant and can do well in unheated room-temperature tanks (mid-60s°F and above). A heater is still nice for stable temps in cold rooms or basements.

Are they good for beginners?
Yes — Zebra Danios are one of the hardiest, most forgiving community fish and are commonly recommended as cycling and starter fish. Just don't overcrowd or skip water changes.

Will they nip fins?
Sometimes — especially in small groups or cramped tanks. Keep them in proper schools (6+) and avoid pairing with long-finned slow swimmers (bettas, fancy guppies, angelfish) and you'll rarely see issues.