For the last week or so I've been finding tiny holes in my plant's leaves but I haven't been able to narrow it down to any cause. I'm not sure if it's WPM or not but I occasionally see a tiny bit of white on my plants and there is a buildup of white dust on the circulation fan and on the top of the cooling fan for my grow light. It's kinda hard for me to describe what it looks like because my camera doesn't pick it up well, with just minor damage and nothing under the leaves. Is this WPM or something else, and how hard would it be to remove from my grow space?