it works for bryopsis (and HA) but the key is you must maintain a level of 1600 or higher for at least 2 wks..then figure out what the source of your nutrients is....I was able to do this as I do NOT keep SPS, only LPS, and it didn't affect them at all.
I am still battling it, but may have found the source of the problem (thanks to Eric-Veralte). I was sparingly using my CL which was causing all my nutrients to stay towards the bottom of the tank and not float to the top into the overflow and into the skimmer.
since I have been running the CL 24x7 for almost a week, I have noticed a slight difference...I added a lawnmower blennie tonite, so hopefully in a couple of days I should noticed the blennie cleaning up the tank...