Are red legged hermit crab sleeping together normal?

[bruhman]

I've had these 5 red legged hermit crabs for a few weeks now, they looked normal up until a few days ago. However, recently they started huddling up together when lights are out. They are out and about as usual during the daytime.

 

[VintageReefer]

Your rock looks fairly new, my guess is they are attracted to an algae or film patch that is growing there

 

[bruhman]

Your rock looks fairly new, my guess is they are attracted to an algae or film patch that is growing there

So they only do it at night when lights are out, they are all over the tank as usual during the day.

 

[VintageReefer]

Maybe they eat it during the night and it regrows during the day
:/

Are they eating in that spot when they are together?

 

[Reefering1]

Geez, how about giving them some privacy