Hey guys, im new to this forum! I just need a few advice on rainbow crabs as i am a novie here.hahaha

Is it suitable to feed my rainbow crabs with guppies or tetra fish? and also is it possible to put a crayfish/yabbie of the same size in the same tank as my 2 rainbow crabs?

Also, one of my rainbow crabs is constantly active and always stay out of the hiding spot while the other keeps hiding in the hiding spot and only comes out when im not near them. When i approach it, it will quickly scramble to hide away from me, unlike the other counterpart hahaha.