I've battled cyano for a while now (nearly a year) in one of my tanks that had live rock which I was given by a friend. After posting and reading many threads, I got much advise ranging from water changes to changing bulbs to increasing flow. Nothing helped at all and it ended up costing quite a bit of money and frustration. It seemed like everyone wanted to blame it on poor husbandry, which couldn't be further from the truth. It wasn't until I read this thread http://www.3reef.com/forums/algae/how-get-rid-cyano-63748.html and Dowtish's advise to use special blend bacterial suppliment that it all seemed to make sense and I can say that my tank is now almost 100% cyano free and my chaeto is now starting to grow again after only a month. I'll chock this up to my tank not having proper bacteria to outcompete the cyano, which special blend was able to provide. I'll continue to use this stuff in this particular tank, but might also pickup some fresh live sand and live rock from other tanks that can provide the proper reef\saltwater bacteria found in wild colonies. Thanks again.