What happens whenever a door opens or closes in the mermaid coral caves?

In the mermaid coral caves, whenever a door opens or closes, a shimmering wave of bioluminescent light ripples through the water, illuminating the intricate coral formations. This phenomenon is accompanied by a gentle, melodic sound, resembling a soft chime, which resonates throughout the caves. The movement often stirs the marine life, causing fish and other creatures to momentarily pause and observe, as if sensing the magic of the moment. The atmosphere becomes charged with a sense of mystery and enchantment, reflecting the hidden wonders of the underwater realm.