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Wednesday, Oct 7, 2026

Fact Brief: Does Santa Clara County give out fish to fight mosquitos?


yes

Santa Clara offers free mosquitofish to all its residents as a way of combating the mosquito population. Santa Clara County vector control gives away mosquitofish to help control the mosquito larvae population in areas of standing water – such as ponds, lakes, watering troughs, unused swimming pools, outdoor spas and rain barrels. 

Mosquitofish are natural predators that eat mosquito larvae. They are small fish, no larger than 2.5 inches in length and are an environmentally friendly control option compared to spraying insecticides. 

Caring for a population of pest-eating mosquitofish is low maintenance. The fish require sunlight pools that are free of chlorine or ammonia and are compatible pond mates to other ornamental fish breeds like goldfish and koi.

Mosquitofish may need supplemental fish food during the winter when insect populations are low. 

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