What are proven ways to control mosquito breeding in outdoor sump wells?
Any sort of screen presents a clogging problem. Each action of the pump may disturb any layer of cooking oil used, or dislodge a mosquito dunk.
I've been told nestling the pump in cobble rocks works, but I'm skeptical. While it may hide the surface of the water, it there still will be a water surface under the rocks. Reference to studies or mosquito control expert opinion would be helpful.