I have used "Blue Vet" red slime remover in the past. It worked really well but I went with 1/2 the recommended dose. It also seemed to have the long term effect of taking out some of my good filtering bacteria as well or killing off enough of something that it started to raise my N levels. It also caused irritation in SPS and total retraction of my yellow polyps for a week or so. I accelerated water changes to give the biological bed a chance to recover. And all was well.