Just to be perfectly clear, breeding goldfish won’t be an easy feat. Livebearers in general are far easier to breed in captivity as opposed to egg-layers like goldfish.
Apart from a large amount of space, a nutritious diet, and excellent water conditions, you will of course need a male and a female goldfish. Consider as well whether you have sufficient space to house the future offspring of your goldfish. You will need a 10- to 20-gallon fry tank, a heater, plants, a sponge filter, and an air pump.
Ensure that your male and female goldfish are sexually mature. Goldfish need to be at least a year old in order to be accurately sexed. Having more males than females in a tank will increase your chances of seeing offspring. However, if you have insufficient space, one pair of goldfish is OK.
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