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Mystery Fish Appear in Pond: Gambusia (Mosquito Fish)

Cleaned filter, found fish swimming. Never added fish. Lily from Menards, plants from garden store. Look like minnows. Bought bloodworms. Asks ID, source, winter care (MN, empties pond).

Gambusia affinis (Mosquito Fish)

Livebearers, eat mosquito larvae.
Came with plants (eggs/fry on roots) or bird-dropped.
Beneficial—reduce mosquitoes.
Eat flakes, bloodworms, algae.

Winter (MN)

Pond emptied → they die. Options: give away, indoor aquarium (tropical setup). Not cold-hardy in frozen ponds.

Great bonus fish for summer!

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