• Step 1:The primary cause of cloudy water is bacterial growth. Bacteria can find their way into feeders from the sugar, the water or even from the hummingbirds' tongues. To decrease the likelihood that the sugar or water introduces contaminants, try to sterilize the solution before filling the feeder. One technique is to simply boil the water and then add the sugar. A second method is to boil the water, add the sugar, and briefly bring the entire solution to a boil. There is no way to control the bacteria brought by the birds themselves.