i just set up 30 gal planted tank and after 1 week the decorative rock started growing 1 to 2 mm white fuzz, it's spreading fast. there are no fish or shrimp yet just a few choice plants taken from my healthy 80 gal tank. I've never had this issue in 28 yrs of tanks, what should i do? or how do i treat ? I've been poking around and have found a few posts with others who have had this but nobody says anything about treating the issue. HELP?