The enjoyment of having Goldfish used to rely on their color and fancy tails. Nowadays, however, there’s a major thrill revolving around how fast and big a Goldfish could grow. This is why we often hear the words stunted, large, and jumbo in Goldfish forums.
In the pursuit of growing a Goldfish to their biggest size, one needs to learn about their growth rate.
WHAT IS “GROWTH RATE”?
The term “growth rate” refers to the speed at which a Goldfish increases in size over time. This rate is influenced by various factors, such as diet, tank size, gender, type, water quality, temperature, and genetics.
The growth rate is a key indicator of their overall health and well-being. In optimal conditions, Goldfish experience rapid growth during their first year. After this initial period, their growth rate slows down. They may continue to grow gradually, reaching their full adult size over several years.
Ultimately, the size of a Goldfish depends on their variety. Common Goldfish and Comets can grow to 12 to 14 inches (30 to 35 centimeters) or more, while fancy Goldfish varieties, like Ranchus or Orandas, typically grow to about 6 to 8 inches (15 to 20 centimeters).
FACTORS INFLUENCING GROWTH RATE
Everyone expects their Goldfish to reach the standard maximum size, but that doesn’t always happen due to several reasons.
MAXIMUM SIZES OF DIFFERENT GOLDFISH
Goldfish come in a variety of types, each with unique characteristics, including their maximum size. Here’s a list of some common types of Goldfish and their typical maximum sizes.
COMMON GOLDFISH
The most basic and hardy variety. Usually orange, but also available in other colors. Maximum Size: 10 to 14 inches (25 to 35 centimeters)
COMET GOLDFISH
Similar to the common Goldfish but with a longer, more pointed tail fin. Often more active. Maximum Size: 10 to 14 inches (25 to 35 centimeters)
FANTAIL GOLDFISH
A fancy Goldfish with a double tail fin and egg-shaped body. They are among the hardier fancy varieties. Maximum size: 6 to 8 inches (15 to 20 centimeters)
SHUBUNKIN GOLDFISH
A variety of Goldfish with calico (multi-colored) patterns and long, flowing fins. Maximum Size: 8 to 12 inches (20 to 30 centimeters)
RYUKIN GOLDFISH
Known for their deep, rounded bodies and a pronounced hump behind the head. Maximum size: 6 to 8 inches (15 to 20 centimeters)
ORANDA GOLDFISH
Recognizable by their wen (a fleshy growth) on the head. They come in various colors. Maximum size: 8 to 12 inches (20 to 30 centimeters)
RANCHU GOLDFISH
A Japanese variety with a rounded body and a head growth, similar to the Oranda but without a dorsal fin. Maximum size: 6 to 8 inches (15 to 20 centimeters)
LIONHEAD GOLDFISH
Similar to the Ranchu but with a more pronounced head growth, often without a dorsal fin. Maximum size: 6 to 8 inches (15 to 20 centimeters)
PEARLSCALE GOLDFISH
Noted for their round, golf-ball-shaped body and raised, pearl-like scales. Maximum Size: 6 to 8 inches (15 to 20 centimeters)
BLACK MOOR GOLDFISH
A fancy Goldfish with a velvety black color and protruding eyes. Maximum size: 6 to 8 inches (15 to 20 centimeters)
BUBBLE EYE GOLDFISH
Known for the fluid-filled sacs under their eyes, they are delicate and should be kept in a tank with no sharp objects. Maximum size: 6 to 8 inches (15 to 20 centimeters)
CELESTIAL EYE GOLDFISH
Unique for their upward-pointing eyes and lack of a dorsal fin. They are delicate and require careful handling. Maximum size: 5 to 7 inches (13 to 18 centimeters)
MEASURING GOLDFISH
The method you use depends on the context or specific guidelines, but “standard length” is more commonly used in scientific contexts, while “total length” might be used in casual contexts.
When measuring a Goldfish, the standard method typically involves measuring from the tip of the nose to the base of the tail (the point where the tail fin meets the body). This measurement is referred to as the “standard length”.
However, some people may also measure the “total length”, which includes the entire length of the Fish from the tip of the nose to the end of the tail fin. This method includes the tail fin in the measurement.
Total length measurements are commonly used for commercial purposes as they make the Goldfish appear larger. However, this can lead to disappointment when buyers receive the Fish and find them smaller than expected.
STANDARD LENGTH Nose to the base of the tail (excluding tail fin)
TOTAL LENGTH Nose to the end of the tail fin (including tail fin)
DOWNSIDE OF FORCE-FEEDING
Force-feeding Goldfish or trying to accelerate their growth unnaturally can lead to several significant disadvantages and health issues.
DIGESTIVE ISSUES
Goldfish have a simple digestive system that can easily become overwhelmed by too much food, leading to digestive problems like constipation and swim bladder disorder.
OBESITY
Excessive feeding can cause the Fish to become obese, which can shorten their lifespan and reduce their overall quality of life.
SWIM BLADDER PROBLEMS
Overfeeding can lead to swim bladder disease. This condition affects the Fish’s ability to regulate buoyancy, causing them to float uncontrollably, swim sideways, or sink to the bottom.
WATER QUALITY ISSUES
More food leads to more waste, which can quickly degrade water quality. Poor water quality results in increased ammonia and nitrite levels, which are toxic to Fish and can lead to stress, disease, and death. Excess nutrients from uneaten food can promote algae growth, which further deteriorates water quality and reduces oxygen levels in the tank.
DEFORMITIES
Rapid or unnatural growth can stress the Goldfish’s organs, leading to malformations such as bent spines, or internal organ failure.
INCREASED STRESS
Forcing a Goldfish to grow too quickly can result in increased stress, which weakens their immune system, making them more susceptible to diseases.
REDUCED LIFESPAN
Health issues can significantly reduce a Goldfish’s lifespan. A healthy Goldfish can live up to 10 to 20 years, but force-feeding can shorten this considerably.
Goldfish competitions promote growth contests for the organizer’s financial gains. As a Goldfish lover myself, I recommend allowing the Goldfish to grow at their natural rate by providing a balanced diet, clean water, and a healthy environment. Forced growth can result in serious health problems, a decreased quality of life, and a shortened lifespan for the Fish.
