what type of food should i feed my corals

[i have crabs]

my tank is mostly softys,leathers,shrooms and zoo's i used to use dt's and it seemed to work well but i was told it was garbage and i shoud use the kent concentrated stuff so i used that for a while and fooled around with the amounts for a while but was not happy with it,so now im using reefroids which seems to be ok but i want to know what everyone else thinks.