What Crabby is doing?

[Gabbone]

Crabby is the first inhabitant of my aquarium and I added her about 2 days ago.

The first day she was very shy and hiding under the rocks or in corners. Now she is exploring, eating a lot and seems overall very healthy. She seems more active when the lights are off. When I turn on the lights she starts to go down and hides. Two blue hermit crabs are coming this evening. I can't wait!

 

[Idoc]

I can't view your added video, but it is pretty normal behavior for crabs to scurry and hide when lights are on or if they notice movement around them.