Goldfish Fry Growth Chart: Track Your Batch Day by Day
Three days after spawning, the eggs still look like tiny beads. Two days later, the glass is covered in slivers that barely move, and you’re wondering if they need food yet.
This chart shows what each stage looks like and what to do about it. The tracker below follows your own batch, so you always know which stage you’re in.
The whole journey
From egg to young fish in six stages
| Stage | Age | What you’ll see | What to do | Sources |
|---|---|---|---|---|
| Eggs | Laying day to about day 5 | Clear to amber beads stuck to plants or a mop. Eggs that are developing show two dark eye spots. | Keep the adults away, keep the temperature steady, and lift out white, fuzzy eggs. | Bristol Aquarists’ Society breeding notes Brazilian Journal of Biology |
| Hatchlings | First 1 to 2 days after hatching | Tiny slivers hanging on the glass and plants while they use up their yolk sacs. | Don’t feed yet. Start hatching brine shrimp so food is ready when they swim. | Bristol Aquarists’ Society fry guide Practical Fishkeeping |
| First foods | First 2 weeks of swimming | Fry leave the glass and swim around looking for food. | Feed tiny meals 3 to 5 times a day: a liquid fry food on day one, then newly hatched brine shrimp. | Bristol Aquarists’ Society fry guide Aquarium Co-Op |
| Growing fry | Weeks 3 and 4 | Fry reach about a quarter to half an inch, and tail shapes start to show. | Mix fine daphnia and powdered food in with brine shrimp, siphon the bottom daily, and change water often. | Bristol Aquarists’ Society fry guide Practical Fishkeeping Developmental Dynamics study |
| Sorting by shape | Months 1 to 3 | Body and tail shapes are easy to see, but most fry are still brown or bronze. Many reach about ¾ inch by six weeks. | Sort by shape if you breed for looks, move up to bigger foods, and give them more room. | Bristol Aquarists’ Society breeding notes Agricultural Marketing Resource Center Maidenhead Aquatics |
| Young fish | 3 months and up | Fish around 1½ inches long. Some start turning from bronze to orange, while others take longer. | Keep up the water changes, give them room to grow, and keep them away from adults until they’re well grown. | Practical Fishkeeping The Fish Vet Aquarium Co-Op |
Free tracker · Saves in your browser
Track your own batch, day by day
Add the day your eggs were laid. Mark hatching and free swimming when you see them, tick off each day’s care, and log counts or test results. Everything saves in this browser, with a backup file you can download.
- Eggs
- Hatchlings
- First foods
- Growing fry
- Sorting by shape
- Young fish
Today
Today’s care
Batch log
No entries yet. Counts and test results show up here, newest first.
How temperature changes hatching time
Warmer water speeds everything up. In a study of goldfish eggs, the first eggs hatched after about 105 hours at 64°F (18°C), 75 hours at 72°F (22°C), and 51 hours at 79°F (26°C).
Too much heat backfires, though. Every egg kept at 93°F (34°C) developed problems and none survived, while the best hatch came at about 75°F (24°C).
First meals and how often to feed
Breeder Bob Jones of the Bristol Aquarists’ Society gives a liquid fry food on the first swimming day and moves to brine shrimp the next morning. He feeds four times a day, roughly every four hours.
Small, frequent meals beat one big feed. Aquarium Co-Op suggests up to 3 to 5 small meals a day, and anything the fry don’t eat should come out before it rots.
How fast fry grow
Growth varies a lot. In a lab study of fish raised one per tank at about 75°F (24°C), fry measured about 7 mm (¼ inch) two weeks after spawning, 11 mm a month after, and 17 mm (⅔ inch) at seven weeks.
Fish raised together in that study grew unevenly, with some far bigger than their siblings. Bob Jones sums up what fry need to grow quickly: good water, good food, warmth, and space.
When to sort by shape and expect color
Fancy tail shapes show early. Practical Fishkeeping describes picking out split tails about two weeks after hatching by looking down on the fry from above, and the Bristol breeding notes add more sorts at 4, 8, and 12 weeks.
Color takes much longer. Fish vet Dr Richmond Loh says most goldfish start changing color at 3 to 6 months or later, and Maidenhead Aquatics notes bright colors can take up to a year.
Keeping the water clean as they grow
Fry eat often, so their water gets dirty fast. Bob Jones runs a slow drip that replaces half the water every day and siphons the tank floors daily.
Without a drip system, Aquarium Co-Op recommends daily water changes, or several a week, in the early days.
Keep your batch on track
Practice first
Try the tricky calls in the goldfish breeding simulator, including its sick fry scenario. If eggs just showed up, start with what to do when goldfish lay eggs.
Plan the food and the next spawn
To grow algae for live foods like daphnia, see how to make a green water culture. For your next planned spawn, learn how to make a spawning mop.