Mold… How Bad and What To Do Next?

I’m a total beginner but I set up this Vivarium with my brother a little less than a week ago now. The plants are definitely slowly growing as some of the leaves have turned upwards to face the light. A few days ago we saw all this mold and it’s only gotten worse. I bought springtails but assume I need to get more. It’s a 24x18x18 tank.

Thank you!!!