2 Beginner Questions

I have 2 questions to ask. The first one is what soil is best to use for young clones and seedlings? My second question is, is a 400w MH that is 24" away to much for young clones and seedlings?

whatever soil you plan on growing in with extra perlite is best.
you could use the MH at a closer level, seedlings do not need weak light.

Why use soil at all go hydro/areo. Ever try Coco Coir? 400w at 24" should be ok but I've grown them at 18" Just depends on what your strain and setup can handle.

400w can go alot closer than that, hold your hand under the light for awhile and see if your hand starts to get hot you know its to close