Me, I have Fathom Hydra LED's, 2 of them. They technically do not cover the entire 72" length but there are just the corners that are shaded about half of the return. Whatever needs less light resides there. I have my Elegance on the right half way into the shade. The lights are super strong though, never go above 70%blue and 50% white, and barely am I that high, the algae growth has my lawnmower blenny nice and fat and always active.