3yr old reef with a lot of cyano on sand, need help

[bitwise]

Posting an update here on progress. I had beaten the cyano to <5% of it's original mass and thought I had won the battle but it came back and resurged (to a much smaller degree than the original amount). I vac'd the sand a couple of more times and kept up with process of 3 - 4 drops of MB7 right out of the bottle.

Happy to update that as of a week ago or so I'm 100% cyano free. This was just done with water changes, sand vac, MB7, diligent skimming, and removing detritus out of my sump.