Species · Danios & minnows
White Cloud Mountain Minnow
Tanichthys albonubes
The hardy "coldwater tetra" — a peaceful subtropical schooler that thrives without a heater, and the humane, tank-appropriate answer to the goldfish bowl. Keep a group.
Difficulty: BeginnerColdwater (goldfish) tank✓ Fact-checked care guide
Quick facts
| Adult size | ~4 cm / 1.6 in |
|---|---|
| Minimum tank | ~40 L / 10 US gal for a shoal — SeriouslyFish recommends a 60 × 30 cm base |
| Temperature | 16–22 °C / 61–72 °F (a coolwater fish; species range 14–22 °C / 57–72 °F — no heater needed) |
| pH | 6.0–8.5 (very adaptable) |
| Hardness | 5–20 dGH |
| Filtration & flow | Cycled, gentle filtration; happily unheated |
| Diet | Micro-omnivore — small flake/micro-pellet plus tiny live/frozen foods |
| Social | Shoaling — keep at least 6–8 |
| Temperament | Very peaceful |
| Lifespan | 3–5 years |
Overview
The white cloud mountain minnow (Tanichthys albonubes) is a small, hardy, peaceful schooler often called the "coldwater tetra". It is genuinely bulletproof and — crucially — thrives at cool room temperatures without a heater.
That makes it the honest, humane alternative to sticking a goldfish in a bowl: a proper coolwater community fish for an unheated tank. As with many popular fish, some farmed stock is inbred and weaker — buy active, healthy fish.
Water & tank
Very adaptable on chemistry (pH 6.0–8.5, 5–20 dGH), and it actively prefers it cool — 16–22 °C / 61–72 °F — so no heater is needed in most rooms. Avoid keeping it warm long-term.
Give a shoal at least ~40 L / 10 US gal (SeriouslyFish recommends a 60 × 30 cm base), cycled and planted.
Feeding
A small-mouthed micro-omnivore — a good small flake or micro-pellet base plus tiny live/frozen foods. Feed small amounts once or twice a day.
Behaviour & tankmates
A peaceful shoaler — keep 6–8+ for colour and confidence. Best with other coolwater-tolerant, peaceful species; don't mix with tropical fish that need warmth, or with goldfish (which will grow to eat them).
What to expect
An active, hardy little fish that colours up (males show a red-tipped fin display) in a settled group. It shrugs off the temperature swings that stress more delicate fish.
Myths, kindly busted
“White clouds and goldfish make good tankmates.”
No — goldfish get large and messy and will eventually eat white clouds; keep white clouds with other small, peaceful coolwater fish.
“They need a heated tropical tank.”
They are a coolwater/subtropical fish that thrives unheated at cool room temperature; keeping them warm long-term is worse, not better.
When to act
We triage, not diagnose — but these are worth a closer look (starting with a water test):
- Kept too warm long-term, they become listless and shorter-lived — check the temperature is in the cool range.
- Pale colour, hiding or clamped fins — test the water and check the shoal is big enough.
Sources & further reading
- SeriouslyFish — Tanichthys albonubes — Adult ~40 mm SL; 60 × 30 cm base; temperature 14–22 °C / 57–72 °F (coolwater, no heater); pH 6.0–8.5; hardness 5–20 dGH; very peaceful shoaling community fish.
Written & fact-checked by The Finfern Team against the sources above — kind, general guidance, not a diagnosis. If something looks wrong, test your water and, if it persists, contact a fish-savvy vet.
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