i have been growing in mg and i have had only a couple of problems but nothing in comparason to paying for the more pricey soil. ff is great if you have the money i really like oc and lw mixed with perilte chuncky but i use mirical grow with 50 percent perilit and mg nuts with ff big bloom. i like it and yes deficiencies do happen but their are some phonomes that take to it better. my bcn auto diesel loves the stuff it is growing very nice. purple #1 is doing ok its strecking. Gigabug is very heat sensitve! anyone getting that strain should know keep it below 85 f i don't know the conversion. Mg is ok to use don't let anyone tell you the best is grow in organic i preffer the taste of organic but if you are trying to just supply yourself on a tight budget do it! save up then get our organic on.