second that, I know theres lots of people that do use mg but theres no real benefits that are worth the hassle imho,
I know people can think that theres a big con with purpose soils from growshops but defo worth using especially for the newer grower, the time release shit can cause you problems do a bit of reading up on it youll see what I mean, as for what to use, if its a seedling get a light soil, which will have enough in it for a couple of weeks or so, most feeds will be ok from then just remember to start with a week feed to see, then up it from there, if you want to go more natural then feed with something like biobizz grow etc,