[header] How to tell if your goldfish is an adult [title] Identify what type of goldfish you have. [step] Different types of goldfish have different characteristics. Understanding what breed you have can help you determine the proper adult coloring and growth for your fish. 
[substeps] If your goldfish is metallic yellow or orange with white markings, it may be a common or comet goldfish. These are marked by their sharp, forked tail.