[ConceptX9]

i would recommend using 12 fluros, this should give you 35400 lumens which would be a bare minimal for your 10 plants, i also suggest putting these fluro's around it like 4 on the sides and 4 on top (good spacing), this will reduce stretching and give light to those hard to reach areas

your going to want to consider mylar as well, put this stuff up on the walls around the whole area your growing in, so you don't waste any light,

i don't know how hot fluro's get so put in a desktop fan to cool things down and to circulate some air for your plants, this also helps simulate outside wind

"during flowering if you only use only MH light your buds will tend to elongate, be less dense and more fluffy, if you use only sodium, you have the potential for growing shorter and denser buds" this is what i heard from experienced growers, if you want to have a good set of buds, i suggest getting the Son Agro Bulb (53,000 lumens) with your 400 HPS, it has both spectrums for one bulb, also your going to use at least 6 of those fluro's too because you have 10 plants, your gonna need a lot of lighting to get the best results

nutes should be used at low doses, i suggest using nutes when your plant is a bit older, maybe around 3 weeks or 4 weeks of growth, hard to say. a hint i would recommend, pick up some epsom salts (Mg), this is an important secondary nute that is commonly over looked, but if you get peters proff. it should contain secondary nutes as noted on the package otherwise if not pick up epsom