FEEDING THE CREATURES
The phasmids are simple- they require fresh vegetable matter. Leaves of bramble/blackberry and its relatives of the genus rubus are suitable. Some species can also handle oak leaves and such. Be sure to properly research your specific species and its natural diet.

The mantids present a unique challenge. Late in life, the feeding is simple. For most specimens, one large cricket per day will suffice. These can be purchased at fishing tackle shops and pet stores.

As it is easier to attain mantid egg cases than it is adult specimens, some planing needs to be given to the hatchlings nutrient source. They will eat each other, moments after being born. The more clever of the lot might even sit at the edge of the case, nabbing siblings as they stumble out into their new lives. For this reason, one must isolate individuals as soon as possible, though it is indeed often not feasable to house 150-200 newborn mantids individually.

Mantid hatchlings, aside from each other, enjoy eating fruit flies and later pinhead crickets.

Above Make sure to allow room for growth

The Practical Alientomologist offers to the student a set of approved links for further study.