wait did it come in a bottle?
if it did then you should take off the top layer of the kunugi so that the soil shows then put in ur larvae.
what kind of larvae do u have? if it is of the dorcus species it is good to use kunugi. but if its a prosopocoilus, cyclommatus, hexarthrius, or lamprima then dont use kunugi. if its a phalacrognathus, allotopus, or a mesotopus then kunugi is practically manditory.