trio

hey guys so i wanted to know if i was able to add a third or maybe fourth gold bar maroon clown to my existing pair?

I just added 3 Dispar anthias three days ago but so far they have only hidden in the rocks and above my powerheads. Aren't these supposed to be open water fish? Is this normal behavior days after adding them? Also what should I feed them? I know in the wild they eat zooplankton but people say...