blackout is a last ditch method for elimiating green water IMNSHO
levels are the problem. testing the tapwater for PO4
exess feeding, built up mlum hiding somewere in the tank, dirty filter housings.
how about cleaning everything real well, doing a very thoral gravel vac and doing some heathy sized water changes.
feeding just enough for the fish to eat in 45-60 seconds while turning off the filter will help as well.
if you still need printed proof, ie the methods above dont work for you, check the local library the blackout method is as old school as UGF