Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
I would do a job of cleaning it off. Just waving your hand by the plants can help, or gently shaking the plants.
With lots of water movement the dust might go away, but I would not leave it to chance.
You could use a slow siphon such as a gravel vac, but do not run it so fast the water sucks in the leaves. Then you are actually removing the dust from the system.