Pet water bowls should be washed every three days to remove potential mosquito eggs. If you have an automatic pet watering bowl, the automatic feature must also be cleaned. On the other hand, mosquitofish can be placed in troughs to prevent mosquitoes from breeding. If you would like mosquitofish, contact our office at 559-732-8606 or through the toll-free number 877-732-8606 during regular business hours.