i struggled with my radion gen3 pro for over a year trying to change settings, intensity, length of time the lights were on, etc. i was never satisfied with the growth of my corals but the colors always looked awesome. i just switched over to a 8blub ati sun power and sold my radion. i think that for me the radion just has too many settings and i just could never find the right one for my personal tank (everyone is slightly different). i had my best lick with the "radiant" setting at 55% intensity about 15" from the water line. also i think part of my issue with the radion was that it doesnt give the coverage that you might think you would get from it...i had 1 gen3 pro over a 66galloon 32x24x20. i think if i turned the light front to back and added a second one i would of had better success than 1 light going length wise. of course you can grown anything you like in the sandbed including acros-lol-but the corals off to the side of the light shield lacked color for sure. i actually added 4 t5 bulbs in additional to the radion and things went alot better for me but at the end of the day its just too much of an energy draw. now i will jsut run the 8bulb sun power with a single strip of the reefbrite blue strip to the front for blue pop. not much less of an energy draw but im curious to see how much more growth i do or dont get with the t5's set up. good luck