Vibrant is not chemicals, its is a patented blend of algae eating bacteria. I have had good experience with it, I dosed it moderately, it does not completely remove hair algae, but makes it weaker and easier to manually remove. If you have refugium, be careful, it is harmful to many macroalgae species, including chaeto. That said, chemicals such as algafix or red slime remover also worked for me, with no bad side effects, but now I use only vibrant since it is more natural. It is best to use it in moderation and monitor the tank carefully, especially initially, some people reported problems with oxygen levels after using it.