Communal species are able to live together without cannibalizing.
⚠ Caution! if they are underfed or if you have large mantids and small nymphs you'll need to reconsider communal rearing. Space or area also is a factor, more area fpr them to perch is important.
See some was we provide more area with mesh inside the habitat.
The species we recommend here are some we've known to be compatible with the same species we don't recommend mixing different species
The rule of thumb when selecting a species for communal living is the 'pinhead' or tiny head and more docile species are best, ie Ghosts
We also have success with many species before they reach adulthood although it's critical for them to have a great area and food that is always plentiful