Cyano is best dealt with by Chemiclean Red Slime remover IMO. But cyano has been in many of my tanks without me needing to use this. I used it once when I just could not control a outbreak. Followed the directions, worked great, reef safe with clams. IMO just wait and see if it becomes more of a problem. Also something like an orange lipped conch is an indispensable member of the sand bed CUC. It will seek and destroy all dark spots 24/7/365
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