overnight i have white specs on my glass. they are to small to photograph and they seem to move around on the glass. in the tank is live rock two feather dusters 8 astera snails. 10 blue legged hermit crabs, 5 white legged hermits, 2 red legged hermits. tank has been set up for about 2 1/2 months now. should i be concerned and what could they be? thanks for your time.