If you’ve just bought a goldfish, you may be wondering: “How long does it take for goldfish to grow?”. Typically, several beginners also share the same concern since they are often unsure about their fry’s growth rate. Some think their goldfish can take several weeks to develop, while others believe their fish can grow within days.
So, if you want to find the one true answer, delve deeper into the article below. Also, enjoy some golden tips we provide about making goldfish thrive faster.
How Long Does It Take For Goldfish To Grow?
● Week 1: When the goldfish fry first hatch, they can measure about 0.2 inches or the size of a grain of rice. However, after 3-4 days, they can almost double in size.
● Week 2: During the second week, the fry should approach 0.6 inches. You’ll also notice that they’ll look like fish, with the tail fin highly defined.
● Week 3: In this week, massive growth should be present. The goldfish are reaching 0.8 inches long. A dorsal fin development is evident as well.
● Week 4: The growth rate begins to slow down as the goldfish nearly reach their maturity. They may only grow by just over 20%, reaching about 0.9 inches. The most remarkable change is in the development of anal and ventral fins.
● Week 5: At this point, all the goldfish will develop their fins. Growth is still slowing down, with around a 20% increase in size.
● Week 6: Around this age, your goldfish should reach around 1 inch long. Nothing significant in size, but their eyes should protrude.
● Week 7: Not much occurs during week 7. They are still juveniles, so you’ll notice more growth.
● Week 8: The goldfish can measure about 1.25 inches, an increase of around 15%.
● Week 9 onwards: The growth rate of goldfish slows down dramatically as they mature. But slowly, they can reach about 2 inches in 6 months and over 3 inches by the end of their first year if provided with sufficient nutrition.
How Can I Make My Common Goldfish Grow Faster?
Goldfish have no stomachs and digest their food in the intestines, making them yearning for food all the time. Since proper feeding can boost the goldfish’s growth, their food should come from high-quality fish. It’s advisable that these fish food have a high level of alkaline and protein rather than tropical fish food, which is not favored by goldfish.
Daphnia and brine shrimp are some typical food to feed the goldfish. They also enjoy smaller fish such as guppies. Besides, since goldfish are omnivorous, they are likely to eat bugs that land in the tank and vegetable matter such as blanched zucchini and deshelled.
However, remember not to overfeed them, as overfeeding can pollute the water and cause the fish to be constipated.
Appropriate tank size
Since many goldfish have the potential to reach a larger size, they require an appropriate tank size and enough water to grow and have space to swim. Besides, the large amount of water ensures a stable condition for fish to live healthily. On the other hand, when confined in a nano tank, fish still grow but at a slower rate. Also, too small space means their activity will be restricted, which stunts their growth.
Hence, you should provide at least one gallon of water per full-grown fish. This gives them enough room to swim and explore the surrounding environment.
Suitable water condition
Maintaining high-quality water is a must since it can affect the goldfish’s growth rate. For example, when toxins are present in the water, the fish are likely to get sick from bacteria, parasites, and fungus. As a result, they have to channel their strength into surviving and cannot grow normally. Therefore, it is recommended to change the water daily to get rid of hormones from the water.
A power filter is worth investing in to maintain stability and clean conditions. In addition, it’s essential to test your tank for ammonia, nitrates, and pH at least every 2 weeks to monitor the tank’s environment and make adjustments if needed.
Goldfish grow best in warmer water temperatures from 68 to 74 degrees Fahrenheit. In such conditions, they consume more oxygen, eat more food, and are generally more active, making them grow faster.
Conversely, they tend to hibernate and grow slower when kept in freezing water temperatures, such as in winter.
How Big Will My Goldfish Grow?
Goldfish can grow anywhere from 2 inches to over 10 inches in a pond. They can even thrive and reach a larger size in nature when given ultimate resources and space. However, because of their genetic restrictions, fancy varieties such as Fantails and Veiltails cannot reach the same length as the average fish.
What Food Makes Goldfish Grow Fast?
Live food with a high protein level, such as bloodworms and earthworms, is perfect for making goldfish thrive faster. Brine shrimp is also a good choice, but it does not have much protein.
Besides, since goldfish are omnivores, they eat both meat-based food and plant. Therefore, to stimulate fish growth, it’s recommended to supplement them with vegetables to increase the fiber content in their diet. They enjoy eating vegetables, including canned green beans, mashed peas, zucchini slices, broccoli, carrot slices, lettuce, and leafy vegetables.
In addition, goldfish always desire food, so they will eat anything coming across when they’re hungry. So if algae are present in the tank, they would be an ideal “salad” for goldfish to enhance their nutrition and grow faster.
Hopefully, you’ve discovered the answer to the question: “How long does it take for goldfish to grow?” and vital information to support your goldfish’s size. If you’re going to speed up the growth process of your fish, remember to supplement them with sufficient nutrition and proper environments when they’re juveniles and see how quickly things happen.
Alex is a pet freelance writer and editor with more than 10 years of experience. He attended Colorado State University, where he earned a Bachelor’s degree in Biology, which was where he first got some experience in animal nutrition. After graduating from University, Alex began sharing his knowledge as a freelance writer specializing in pets.