- Step 1
Keep male and female goldfish in separate tanks before choosing breeding pairs. Feed them regularly with high quality dry and live food like brine shrimp and live black worms.
- Step 2
Set up a breeding tank with fresh water and good aeration devices. Include aquarium plants that can serve as places for the goldfish eggs to adhere.
- Step 3
Adjust the breeding tank's temperature to about 64 degrees F. Make sure that the temperature in your main goldfish tanks is also 64 degrees; if not, plan ahead and slowly raise the temperature in the tanks by one or two degrees every day over a six week period.
- Step 4
Choose breeding goldfish in late spring or early summer. Select three males that have hard, white round growths on their bodies and two fertile females with plump abdomens and left sides. Introduce them into the breeding tank between 5 pm and 7 pm.
- Step 5
Turn up the temperature in the breeding tank until it's 68 degrees F. The temperature change encourages breeding activity. Daily 20 percent water changes can also convince your goldfish that it is breeding time.
- Step 6
Wait for the female to lay eggs and the male to fertilize them.
- Step 7
Return the breeding goldfish to the main tank three hours after spawning has occurred.
- Step 8
Turn the temperature in the breeding tank back down to 64 degrees. Allow the eggs to incubate for eight to nine days. Add one drop of 1% Methylene Blue per gallon of water to the tank.
- Step 9
Watch for hatching after five days. Allow the fry three days to complete their hatching cycle.
- Step 10
Feed the fry live food in the form of infusorians, very young brine shrimp, and sifted daphnia. Finely ground dry food may be fed to the goldfish after a week.