Hello everybody, its me again

Yesterday I have bought two tubes of sprintgails cultures and reading now in Internet about feeding them and making culture to grow. Everybody shows different ways, somebody says feed with 100% pure brewers yeast. , other fish flakes , third milk free oats.
And about base: people says use ''We suggest using charcoal as a substrate to breed springtails over coconut fiber & other mixed media.'' others like in this video : Making New Springtail Cultures - "collembola" Part 1 - YouTube Use peat based substrate. So which receipt you can advice to me please?