I am really sorry about that!. Must have skipped that line.
Personally, and factually, you will get the best benefits using both therapies. Blue light is known for killing acne-causing bacteria by creating oxygen molecules.
However, where red light comes to play is for its healing and anti-inflammation property. Red light heals up acne faster and helps you in a multi-purpose way.
Nikki. As far as I know both therapy does not have any bad side effects when it comes to healing your acne marks. Both blue and red light are beneficial. They just have a different effect to how you will use it. Red light has a slightly longer wavelength than blue light.