i wouldnt jump to chemiclean.. best to let it settle out naturally. blow it off during water change, lower your phosphate, maybe increase flow a bit to affected areasLooks like Cyano, bacterial. Lowering phosphates can take care of it, or Chemiclean.
Going the chemical route is overkill.. Cyano is a natural part of the cycling/ugly stage.. it's usually a sign of an imbalance, whether it be nutrients or bacteria.. tons of people use chemiclean, i'm just suggesting to apply some patience first and try waiting it out before dropping the hammerRed slimy stuff. Whats wrong with just treating with chemiclean