The fascinating and exceptionally scholarly goldfish

Goldfish, scientifically known as Carassius auratus, is a phenomenal fish. Their capabilities are amazing, which definitely makes them worth getting to know better.

A Bit of Goldfish History

Goldfish were domesticated in China over a thousand years ago. Initially, they were bred from the Prussian carp (Carassius gibelio). They were valued for their color mutations, especially the orange and yellow ones, which contrasted with the typical silver color of their ancestors. The breeding of goldfish became a popular hobby among wealthy people during the Song Dynasty. Over the centuries, these fish were selectively bred to enhance their colors and fin shapes. In the 17th century, goldfish spread to Japan, and later to Europe and America, becoming a global phenomenon.

What types of goldfish are there?

There are many types of goldfish, each with unique features. Some of the most popular include:

• Comet: Known for its long, smoothly flowing tail and lively swimming.
• Oranda: Characterized by a distinct, raspberry-colored growth that covers its head.
• Ryukin: Has a high back and deep body, often with long, smoothly flowing fins.
• Shubunkin: A single-tailed goldfish with a colorful pattern and a semi-transparent body.

Each species has its unique aesthetic characteristics, from elegant Veiltail fins to the massive, round bodies of Lionhead fish.

Cognitive Abilities of Goldfish

Memory Span

Contrary to the popular myth that goldfish only have a memory span of a few seconds, studies have shown that goldfish can remember information for several months. Experiments have proven that goldfish can be trained to navigate mazes or perform specific tasks that they remember even after long breaks from training. This refutes simplified views about their memory capabilities and points to a more complex neurological basis for their behavior.

Training and Tricks with Goldfish

Goldfish can be trained to perform various tricks through positive reinforcement, which is currently popular in dog training. They can learn to swim through hoops, push balls to a goal, and respond to color signals associated with feeding. This training is based on their ability to associate actions with rewards, which is typical for classical and instrumental conditioning processes, similar to those observed in many higher vertebrates.

Social Learning

Goldfish also show behaviors related to social learning; they can learn from their peers. For example, if one goldfish learns to solve a problem to obtain food, others who watch can learn this solution much faster than those who did not have such an opportunity. This suggests that goldfish are aware of their environment and can also incorporate observational learning into their repertoire.

Spatial Awareness and Navigation

Studies have shown that goldfish have excellent spatial awareness and can remember the layout of their surroundings. This ability helps them effectively navigate their aquariums or ponds, avoid obstacles, and find interesting places (e.g., feeding spots). These abilities suggest the process of creating mental maps, which was once thought to be characteristic only of mammals.

Emotional Learning

Studies suggest that goldfish can experience some form of emotional learning, which involves associating specific stimuli with negative or positive experiences. For example, they can show signs of stress or excitement based on previous experiences that were frightening or rewarding. These emotional reactions can influence their behavior patterns and decision-making, suggesting a level of psychological complexity traditionally not attributed to fish.

Given these capabilities, it is clear that goldfish possess a level of intelligence and learning ability that deserves respect. They are capable not only of basic survival behaviors but also of more complex processes involving memory, learning, social interactions, and even emotions.

Caring for Goldfish

Since we have explained that goldfish are very capable of learning, intelligent, and exhibit social behaviors, it's important to note that although they are often portrayed as easy to breed for beginners, they deserve the best care.

Choosing a Goldfish

• Species: There are many species of goldfish. Choose healthy fish from reputable breeders. Look for active fish with bright, clear eyes and full, healthy fins.
• Number: Remember that goldfish grow large and are social beings. Start with a spacious aquarium that will provide them with room to grow and potential companions.

Preparing the Aquarium

• Aquarium Size: Contrary to popular myths, goldfish need a lot of space due to their potential size and waste production. One goldfish should have at least 75 liters, and each additional one requires another 38 liters. Definitely forget about a small, round aquarium.
• Filtration: Use a strong filter, as goldfish produce a lot of waste. Biological and mechanical filtration is crucial.
• Aeration: Ensure adequate aeration using an air pump or a filter that moves the water surface.
• Decorations: Use smooth, rounded decorations so the fish cannot get injured. Goldfish will appreciate decorations and plants (preferably live, but artificial is also fine), which they can explore.

Water Quality

• Temperature: Maintain water temperature between 18°C and 24°C. Goldfish are cold-water fish and do not need a heater, but a stable temperature is required.
• pH and Hardness: Maintain pH between 7.0 and 7.4. Goldfish thrive in soft water.
• Regular Water Changes: Perform weekly water changes, ideally 10-20%, to keep ammonia, nitrite, and nitrate levels low.

Feeding

• Diet: Feed goldfish a balanced diet of high-quality pellets or flakes, ideally specifically designed for goldfish. Supplement their diet with vegetables (such as peas and lettuce) and protein, e.g., shrimp or daphnia.
• Frequency: Feed small amounts two or three times a day, only as much as they can eat in two minutes.

Ensuring Health

• Observation: Regularly observe your fish for signs of stress or illness, such as lethargy, breathing at the water surface, or clamped fins.
• Quarantine: New fish should be quarantined for at least two weeks before being added to the main aquarium to prevent the spread of potential diseases.

Regular Maintenance

• Cleaning: In addition to weekly water changes, regularly clean the aquarium, substrate, and decorations to prevent the accumulation of harmful substances.
• Equipment Check: Regularly check and maintain the filter, air or water pump, and other devices to ensure they are functioning properly.

Social Interactions

• Aquarium Companions: Goldfish are generally peaceful but can compete during feeding. Choose companions who are not too small to avoid being eaten and who can function well in similar conditions.

Cultural Significance of Goldfish

Goldfish have diverse cultural significance around the world. In China, they are a symbol of wealth and prosperity. During the Chinese New Year, decorations featuring goldfish are common because they are believed to bring luck.

In Japan, goldfish are often associated with summer festivals and even have their place in public spaces, such as the Goldfish Plaza.

Summary

Goldfish are not just decorations; they are creatures with a rich history and diverse genetic origins. For centuries, they have adorned water gardens and homes, bringing beauty and a sense of peace to those who watch them. Whether they are kept in a simple aquarium or a large pond, they deserve proper understanding and appropriate care.