When i had only three basking levels inclueding the floor the only time my Rhino would go under the Mega Raw was when he was in the shade of a log i HAD on the second level on the left . It was 16'' below the mega ray and 100-120 MW of UVB .he could have climbed on the log and got 150+ MW of uvb but never did .he avoided that spot like a plague. SO I tried something , i added another basking rock , the one he is sitting on and raised it up under 100 watt SolarGlo at 80 MW of UVB so he has 4 levels including the floor for heat and UVB . He now will stay under the solar glow for a while then move to the right top rock under the 10,0 48'' zoo-med repi-sun tube and 50 watt halogen bulb . He never stayed under the mega ray at any level, only under the log in the shade . so i removed the mega and put it back in the box . :huh: