Six kid-friendly rewrites
Here are six easy sentences that say the idea in different ways:
After the night, moray eels hide in coral crevices during the day.
Moray eels hunt at night and hide in coral crevices when the sun comes up.
Nighttime is when moray eels hunt; daytime finds them in coral crevices.
Moray eels go hunting at night and hide in small coral holes during the day.
Moray eels hunt after dark and rest in coral crevices in daylight.
When it is night, moray eels hunt; in the day, they hide in coral crevices.