For what it’s worth way back when I was looking into Kent Biosediment for my refug . I mailed Kent marine asking about 24/7 lighting for the refug. This was their response that I kept in my notes “ One thing to remember is to never, never, never run the lamps 24 hours a day… NEVER! Just like plants, algae need a break from photosynthesis, and keeping the lights on all day and all night will cause the algae to enter a reproductive phase (i.e. they turn milky-white and disintegrate, releasing nutrients back into the system and lowering water quality). The best idea is to have the refugium lights (a pair of 6,500K tubes is usually ample) on 8-10 hours a day, or rather night (when the lights in the main aquarium are off).