Hi Marko,
From what I could see of your tank the other night, you definitely have cyano. The overfeeding has put a lot of nutrients into your tank. Cyano has developed as a way of utilizing the extra nutrients. A turkey baster will blow the stuff off your corals, rock and sandbed, but you must be able to export it once it gets into your water column - either with serious skimming or by frequently cleaned mechanical filtration, or both. And, do several 25% water changes over the next few days to severely reduce the nutrients. HTH
