Good choice. Go organic, and stay away from anything that will burn your plant. (Mirical Grow is a big no no). I don't really put much time into the soil I use, maybe a mistake maybe not. Also, put a few holes in the bottom of the bucket so the water has an escape, it will prevent over watering and flooding.
Fox Farm Ocean Forest, or Happy Frog, with about %10 more perlite is what I recommend. Rocks at the bottom for drainage, make sure you make at 10 holes on the bottom evenly, and its good to even drill some small holes on the sides to help the bucket breathe as plastic doesnt breathe like clay does.
I know FF Ocean forest is supposed to be really good.. but would you recommend it for starting plants? If not, what soil would you guys recommend? (Sorry to hijack your thread dude)
Ocean Forrest rules on most strains. The key word here is "most". You want to be careful when and if you decide to add nuts since the fox farms soil is so rich.
I would go with Fox Farm Happy Frog Soil Conditioner... It does not have as many nutes as FF Ocean Forest, which will treat your sprouts well... You can always add more nutes as you go...