How to keep a Ranchu goldfish?

The Ranchu is a sensitive goldfish; any care mistake can cause illness or death. It dislikes high water and strong flow, so keep water under 40 cm. It needs clean water with regular changes and bottom siphoning.

Aging water for 3 to 5 days before changing, by season. As an omnivore, feed bloodworms or pellets, but not too full; feed small amounts often.