Ah, the Japanese ranchu fish ! A real aquatic jewel that's turning heads on our shelves. As an avid aquarist, I can't help but marvel at these little marvels. Let me tell you the fascinating story of this "king of goldfish", which is all the rage in Japan and is beginning to conquer our Western ponds.
Unique features of ranchu
Special morphology
Ranchu isn't just any fish! Imagine a golden egg swimming gracefully in your aquarium. Its compact, rounded body, with no dorsal fin, gives it a unique look. Its broad head has a protrusion called a "bonnet", less pronounced than that of its cousin the Lionhead. And what about its tail? Short, forked and slightly raised, it adds a touch of elegance to its silhouette.
Colour palette
Ranchu is a veritable aquatic rainbow! They come in all colours, from flamboyant red to immaculate white and deep black. Enthusiasts love the two-tone or calico specimens, which are veritable living works of art. I even had a customer who was desperately looking for a ranchu in the colours of his favourite football team!
Size and longevity
Don't be fooled by its small size! The adult ranchu can grow to between 13 and 20 cm, making it a medium-sized fish. In terms of longevity, these little companions can keep you company for 8 to 15 years if you take good care of them. That's almost as long as a Hollywood wedding!
Maintenance and care of the ranchu
Ideal habitat
The ranchu is something of a pond diva! It needs a heated freshwater aquarium, with a temperature of between 17 and 28°C. Don't skimp on space: allow at least 50 to 100 litres per fish. These little swimmers love to have room to waddle! Here's a table summarising the ideal conditions:
| Parameter | Recommended value |
|---|---|
| Minimum volume | 50-100L per fish |
| Temperature | 17-28°C |
| pH | 6,0-7,5 |
| Hardness (GH) | 5-15 |
Food and behaviour
The ranchu is a real gourmet! Its omnivorous diet requires a high vegetable intake. In my department, I always offer a variety of suitable foods:
- Special flakes for goldfish
- Plant-rich granules
- Fresh supplements (spinach, lettuce, cucumber)
When it comes to behaviour, the ranchu is a true zen! Its slow, graceful swimming adds a touch of serenity to your aquarium. But beware, these fish are sociable: keep your group to a minimum of 2 to 5 individuals to ensure their well-being.
Maintenance and precautions
Ranchu are a bit like temperamental stars: they need to be pampered! These fish are sensitive to infection, so it's crucial to keep the water clean and well filtered. A good filtration system and regular water changes are essential. And don't forget oxygenation: these little swimmers love bubbles!
If you plan to install them in an outdoor pond, make sure the temperature remains stable above 15°C. I've seen ranchus turned into living ice cubes by an owner who was too optimistic about the weather!
The interesting history of ranchu
Ranchu is a bit like the carp gratin ! Native to China and Japan, it is the result of meticulous selection of common goldfish. Its Latin name, Carassius auratusThe Koi is a member of the noble Cyprinidae family, alongside its cousins the Koi carp. In fact, if you're a fan of the latter, I recommend you take a look at our complete guide to choosing your koi carp.
In Japan, the ranchu is considered to be the "king of goldfish". It is so popular that competitions and exhibitions are even organised in its honour! I was lucky enough to attend one of these events during a trip to Japan, and believe me, it was as serious as a haute couture show!
You will sometimes find it under other names such as Katakana or 'buffalo head'. Personally, I prefer 'ranchu', which sounds like the name of a water samurai!
The ranchu, star of your aquarium
As a department manager, I can only recommend that you include these little marvels in your aquarium. Their presence will bring a touch of exoticism and elegance to your home. Just remember that these fish require a little special care and attention.
With its rounded forms and graceful swimming, the ranchu is a real spectacle. It will quickly become the star of your aquarium, attracting all eyes and arousing the admiration of your guests. So, are you ready to dive into the adventure of the Japanese ranchu fish ?
Don't forget: a happy ranchu is a happy aquarist! Take care of them, and these little treasures will repay you a hundredfold in beauty and serenity.
External sources :
wiki aquaculture
wiki fish farming
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