Has anyone experienced this? I have added the caribsea liferock on 3 separate tanks and after a few days later all 3 tanks had cyano. They are all separate tanks so there was no cross contamination. My tanks had been cyano free since setup. Weird part is cyano only appears on the caribsea rock surfaces. Is caribsea a sponsor here on the forum? Seems like they spray something on the rocks that contributes to the cyano since those rocks after blowing them out of cyano their coraline coating or whatever they spray also disappeared. Now I am battling a huge cyano outbreak on one of my big tank.