Is this a new tank? If you are talking about the "Dust" on your leaves, it look like new tank detritus. Insufficient water flow around your tank is most likely. If you are talking about the fuzzy stuff on your roots, same thing, trapped detritus feeds algae.
I add a similar situation which led to a hair algae outbreak. I added a wave maker and made sure my plants had a slight sway and the problem was seriously reduced. Now you can tinker with the duration of the lights if algae really becomes an issue.
Todd