National Geographic said while a goldfish typically weighs just 0.2 to 0.6 pounds, they can weigh more than five pounds in the wild, CBS News reported.
"They grow bigger than you think and contribute to poor water quality by mucking up the bottom sediments and uprooting plants," the City of Burnsville, Minnesota, tweeted on Friday, July 9.
In recent years, huge goldfish were also reported in bodies of water in South Carolina, Missouri, Virginia and Kentucky, CBS News said.
Large, invasive goldfish have also been seen in New York. In March, an angler in Syracuse reported that he caught a 14 1/2 inch goldfish Onondaga Lake, according to Syracuse.com.
U.S. Fish and Wildlife Service has posted guidance on how goldfish owners can "break up" with their pet without damaging the ecosystems of any bodies of water. The agency said after freeing your pet, it can still grow huge under the right conditions.
"Imagine a goldfish the size of a football and weighing four pounds," the agency said.
Some alternatives include rehoming the fish or donating it to a school, learning institution or pet store.
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