We are having a problem with our edger (CPE-4000) leaving spots on our lenses. They don't want to wipe off with normal cleaning techniques or alcohol but can be rubbed off with a fingernail.
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This is on a finished SV poly lens. The spots seems to have an almost oily consistency to them once you "scratch" them off with a fingernail. We have changed the water in the tank to no avail. Does anyone know what might cause this?