Spring tail questions :)

hi all,

i have 4 culturs of spring tails for my dart frogs at the moment, and im having a bit of trouble in trying toget them to increase in numbers.

at the moment im keeping them in moist peat and feedin them potateo skins and dried yeast.... and sprayi them to keep humidity up in a margarine tub

any ideas on how i might get them to produce more ?

cheers

Jonny