Had a sick finch at my feeder in Tucson last month, and it spread fast
I saw one house finch with crusty eyes on a Tuesday, and by Friday three more looked the same. Has anyone else dealt with this finch eye disease and know how to clean feeders to stop it?
My neighbor in Phoenix had the same thing wipe out half her finch flock last spring. Soap and water is like using a band-aid on a broken leg. You need a serious bleach soak, like one part bleach to nine parts water, for at least ten minutes. Let it dry completely before you put it back up.
That sounds rough, but is it really that big of a deal? Birds get sick in the wild all the time, it's just nature. Maybe just give the feeder a good scrub with soap and water.