Help and Advice

Hi guys can someone please positively identify what this is. I've been battling it for weeks now. I've turned my main light off and just had antinics running and it died back quite a lot to the point it was almost gone. I was told in another thread it was cynobacteria so after a long think, I decided to use red slime remover to make sure it didn't come back and that was 2 weeks ago. I put the main lights back on 4/5 days ago and it's grew back just as bad.

Help, how can I get rid as if I...