After initial setup and cycling of my tank I inadvertently introduced Bryopsis into my tank from the LFS. I used the Fluconazole treatment to get rid of it and it worked amazing, I also found that during the treatment the Fluconazole did a great job of removing the GHA that started showing up in my tank. That was 6 months ago and I haven't had a problem since (as far as Bryopsis or GHA are concerned or any other types of nuisance algae). Here is great read for the Fluconazole, you might try that.
https://www.*********.com/threads/br...nazole.285096/