I have this stuff around the top of my tank floating for awhile, Cant figure it out why its there. I had my tank aerated last night because of the Chem-Clean stuff for the red slime. I turned the skimmer back on and they subsided, now they are back as they were last night, no idea why. Moved the two Korolla Powerheads (1's) around but nothing seems to work. Any suggestions?