Ranchu (fancy)
Carassius auratus
The Ranchu (fancy) (Carassius auratus) is a peaceful fish that's a good step up once you have a little experience. Give it a tank of at least 140 litres (37 US gallons), water held at 61-73°F, and a pH of 6.5-8.
Captive lifespan reflects typical experience in a home aquarium, not maximum recorded age; genetics, sourcing, and care vary.
Natural distribution
East Asia
- East & Southeast Asia
Regional colours match the stocking calculator's origin map.
Ranchu (fancy) Tank Setup
Goldfish need at least 140 litres (37 US gallons) with powerful filtration and cooler water around 61-73°F, pH 6.5-8. They produce far more waste than most tropical fish, so don't skimp on the filter. They reach about 15 cm as adults, so don't be misled by the small juveniles sold in stores.
What Do Ranchus Eat?
They're not fussy eaters - feed a varied diet, rotating good-quality dry, frozen, and gel foods rather than the same thing every day, and match the food size to their mouths.
Ranchu (fancy) Tank Mates
Very slow; best with gentle fancy goldfish; avoid strong flow The Ranchu (fancy) is peaceful, which is the first thing to weigh up when you choose tank mates. Good matches come down to the whole stocking list working together - temperature, tank size, and temperament - not any single label. Before you buy, run your full stocking list through our stocking calculator. It weighs temperament, adult size, and water needs together, which a single species page can't do on its own.
Are Ranchus Good for Beginners?
Doable once you test water regularly and catch problems before fish look sick. If this is your first tank, pick something more forgiving and come back later.
Ranchu (fancy) - frequently asked questions
What size tank do Ranchus need?
Ranchus need a tank of at least 140 litres (37 US gallons). A bigger tank is always easier to keep stable, and gives them more room to settle in and behave naturally.
What water parameters do Ranchus need?
Keep them at 61-73°F with a pH of 6.5-8, steady rather than chased to an exact figure. In a cycled tank, ammonia and nitrite should both read 0 ppm, with nitrate kept low through regular water changes.
What do Ranchus eat?
Ranchus are omnivores and aren't fussy eaters. Feed a varied mix of good-quality dry, frozen, and gel foods, and match the food size to their mouths. Feed small amounts once or twice a day, and remove anything they don't eat.
Are Ranchus good for beginners?
Ranchus are best for keepers with a little experience. They are manageable once you test water regularly and catch problems early; a complete beginner may prefer something more forgiving first.
Common mistakes with Ranchus
- Underestimating tank size - the minimum footprint is 140 litres (37 US gallons); impulse buying into a smaller tank leads to stress and shortened lifespan.
Building a community? Run the full list through the stocking calculator before you add anything else.
Great tank mates
Chosen from temperament, overlapping temperature/pH bands, plausible minimum tank footprints, and size versus yours in App-aquatic data. Hobby nuance always wins - verify stocking and temperament before purchasing.
Fish to avoid mixing with Ranchus
These well-known species are commonly sold alongside this fish but are not recommended tank mates - verify before purchasing.
- OscarTropical fish - too warm for goldfish tanks
- AxolotlTropical fish - too warm for goldfish tanks
- Akar BettaTropical fish - too warm for goldfish tanks
