BTW, when using that chemical, if you do, be ABSOLUTELY SURE to monitor your nitrates, AND also THOROUGHLY READ THE DIRECTIONS. If you mess up you will deplete the oxygen in your tank, and EVERYTHING will suffocate, i overdosed purposely in a test tubberware with some aptasia. not a pretty sight. This product also takes a few days to work, but the first sure sign is the cyano starting to desintegrate, like its just dissolving.