How to Tell if Your goldfish is an adult

A goldfish is everyone's first pet because they're easily purchased, easily managed and they don't require being walked. While they are so simple to find, buy and take care of, goldfish (like any living creature) require proper care. The more you know about your fish, the more you can handle it properly. One important fact is whether or not your goldfish is full grown.

Things You'll Need

  • Goldfish
  • Aquarium
  • Fish care information
  • Fish net (possibly)
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Instructions

    • 1

      Determine what type of goldfish you have. Finding out what type of fish you have will help you determine not only it's age but other important details about your pet and its well-being and life cycle. You can check with the pet store you bought it from or any pet book or website.

    • 2

      Take a look at the fish's color. Most goldfish are bronze colored if they are young. As they grow and mature, their color changes to a more golden color with a metallic hue.

    • 3

      Take a look at the size. Once you've determined the type of goldfish you have, you should also know the size it will grow to. Some gold fish can reach an adult size of 12 inches. It will be important to know how big it should get.

    • 4

      Look at the fin on the back of the fish. Young goldfish have more rounded back fins as opposed to adults whose rear fins are more sharp and pointed in appearance.