I tried the 24/7 and I now run them about 13 hours a day. I believe the macro algae needs a rest period just like everything else. I am sure someone has done a study on it somewhere 
Mine has started growing better with the lights on a timer.
Jim
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90 Gallon glass, 135#'s of rock and 2" sand. 2-250w 20k XM metal halides. 2-95 watt actinic VHO, 4 powerheads, Coralife skimmer. Maroon Gold Striped Clown, Blue Chromis, Kole Tang, Pygmy Angel, Serpent Star, Brittle Star,Gorgonians, Mushrooms, Yellow Polyps, Turbo Snails & Blue Legged Hermits. 20 gal sump with Caulerpa, Mag 7 return pump. |