I am not the scientist but my battle with red slime I found it to never grow in the dark.
In fact in the morning when the lights first came on it always had reduced.
It would grow and sometimes double growth during the day to make up for it though.
I am not a fan of additives so I got rid of it by doing the following.
Eliminating all the white light spectrums.
Went with 100% blue spectrum lighting.
Reduced the lighting schedule by 1 hour a day.
I feed frozen foods, so I take PE Mysis shrimp, brine shrimp, LRS herbivore, Spirolina, Selcon, and Garlic. Mix it into a paste spread that into silicone 1/4 inch cube ice trays and freeze it.
I take 6 cubes melt it in a small cup of tank water and dump it in twice a day.
However to rid myself of Cyano I melted the food and then sifted it through a fine net removing the liquids and just feeding the solids.
I also upped the game in my sump and built an algae scrubber with a Kessel 360.
Literally in two weeks it was gone 100%.
Thanks for the advice I am using 40% white spectrum so I could try removing that to see if there is any change. I have wondered about putting the food through a mesh filter before, another thing I should try then ! Cheers