Pretty much all my corals close up or sleep so to speak at night under my moonlights. And during the day everything is wide open looking awesome. My brains, mushrooms, rocordias etc all get smaller in size under the moon. It's completely normal.
"When creating an aqua scape, strive for the beauty of imperfection, as its art and there is no wrong or right, it's left open for interpretation" James Findley