I didn't add anything to the mixture. It has a soil mixed in it already. It just so happens to have alot of organic material in it also. I picked this soil because I have found that whenever something works with tomatos it works with mj. Also, when these are planted they will be in this type of a soil outside. The drainage is very good with this soil, probably too much so. The nutes shouldn't be bad in the sense of too much seeing as if they were planted outside from seedlings they would get the same.
Edit: it also seemed like it would be really airy but when i watered the soil before planting it compacted very nice. I'm not sure why all the big wood chips ended up on top, but underneath isn't so bad. The wood chips are much smaller.