spring tails

I added springtails and isopods to my tank about 3 weeks ago. Every couple of days I turn over a piece of cork bark, or look under the leaf litter, to check on the little guys. The isopods have seemed to be doing pretty well but I haven't been able to spot any springtails...until today...

Ahoy, dendomateys! Total beginner here (I actually don't even have any of my setup yet, just doing lots of research) so I'll probably be posting here a lot in the coming weeks and months. My first question is about invertebrate cultures. It seems like a lot of advice I can find online is...

I bought a culture online, I was just curious if i could transfer some of the culture to a container with Eco earth? And if they could start a new culture on it? If not what is a good(cheap) substrate that works well. I know charcoal does. Thanks